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I have a very long and repetitive python path, where do I look to correct this?

- by ninja123

I know it is probably not necessary to paste the whole path, but just for the record I have done so below. Whenever I run a python command, it takes a long time to load this path I suppose. I have checked in .bash_profile and only have these two lines: export PATH=/Users/username/bin:/opt/local/Library/Frameworks/Python.framework/Versions/2.5/bin:/opt/local/bin:/opt/local/sbin:/opt/local/apache2/bin:$PATH export PYTHONPATH=/opt/local/lib/python2.5/site-packages/ And my python path as outputed by Django's debug is: Python path : ['/Users/username/Sites/videocluster/eggs/ipython-0.10-py2.5.egg', '/Users/username/Sites/videocluster/eggs/South-0.6.1-py2.5.egg', '/Users/username/Sites/videocluster/eggs/django_markitup-0.5.2-py2.5.egg', '/Users/username/Sites/videocluster/eggs/DateTime-2.12.0-py2.5.egg', '/Users/username/Sites/videocluster/eggs/Markdown-2.0.3-py2.5.egg', '/Users/username/Sites/videocluster/eggs/PIL-1.1.7-py2.5-macosx-10.5-i386.egg', '/Users/username/Sites/videocluster/eggs/djangorecipe-0.20-py2.5.egg', '/Users/username/Sites/videocluster/eggs/zc.recipe.egg-1.2.3b2-py2.5.egg', '/Users/username/Sites/videocluster/eggs/zc.buildout-1.5.0b2-py2.5.egg', '/Users/username/Sites/videocluster/eggs/pytz-2010h-py2.5.egg', '/Users/username/Sites/videocluster/eggs/zope.interface-3.6.1-py2.5-macosx-10.5-i386.egg', '/Users/username/Sites/videocluster/eggs/setuptools-0.6c11-py2.5.egg', '/Users/username/Sites/videocluster/parts/django', '/Users/username/Sites/videocluster', '/Users/username/Sites/videocluster/bin', '/opt/local/lib/python2.5/site-packages/setuptools_git-0.3.3-py2.5.egg', '/opt/local/lib/python2.5/site-packages/pysqlite-2.5.5-py2.5-macosx-10.5-i386.egg', '/opt/local/lib/python2.5/site-packages/CouchDB-0.5-py2.5.egg', '/opt/local/lib/python2.5/site-packages/httplib2-0.4.0-py2.5.egg', '/opt/local/lib/python2.5/site-packages/PyYAML-3.08-py2.5-macosx-10.5-i386.egg', '/opt/local/lib/python2.5/site-packages/simple_db_migrate-1.2.8-py2.5.egg', '/opt/local/lib/python2.5/site-packages/PyDispatcher-2.0.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/pyOpenSSL-0.9-py2.5-macosx-10.5-i386.egg', '/opt/local/lib/python2.5/site-packages/greenlet-0.2-py2.5-macosx-10.5-i386.egg', '/opt/local/lib/python2.5/site-packages/Supay-0.0.2-py2.5.egg', '/opt/local/lib/python2.5/site-packages/configobj-4.6.0-py2.5.egg', '/opt/local/lib/python2.5/site-packages/Fabric-0.9b1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/fudge-0.9.3-py2.5.egg', '/opt/local/lib/python2.5/site-packages/pydelicious-0.5.3-py2.5.egg', '/opt/local/lib/python2.5/site-packages/feedparser-4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/github_cli-0.2.5.2-py2.5.egg', '/opt/local/lib/python2.5/site-packages/simplejson-2.0.9-py2.5-macosx-10.5-i386.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', ......(repeating)....... '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', 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'/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', ......(repeating)....... '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', '/opt/local/lib/python2.5/site-packages/setuptools-0.6c11-py2.5.egg', '/opt/local/lib/python2.5/site-packages/zc.buildout-1.4.1-py2.5.egg', 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'/opt/local/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-tk', '/opt/local/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-dynload', '/opt/local/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/Numeric', '/opt/local/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/PIL', '/opt/local/lib/python2.5/site-packages/PIL', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', ......(repeating)....... '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/lib/python2.5/site-packages/gtk-2.0', '/opt/local/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/gtk-2.0'] Someone, please tell me where I can go to correct this. Thanks

Read the article
ASP.NET Controls – CommunityServer Captcha ControlAdapter, a practical case

- by nmgomes

The ControlAdapter is available since .NET framework version 2.0 and his main goal is to adapt and customize a control render in order to achieve a specific behavior or layout. This customization is done without changing the base control. A ControlAdapter is commonly used to custom render for specific platforms like Mobile. In this particular case the ControlAdapter was used to add a specific behavior to a Control. In this post I will use one adapter to add a Captcha to all WeblogPostCommentForm controls within pontonetpt.com CommunityServer instance. The Challenge The ControlAdapter complexity is usually associated with the complexity/structure of is base control. This case is precisely one of those since base control dynamically load his content (controls) thru several ITemplate. Those of you who already played with ITemplate knows that while it is an excellent option for control composition it also brings to the table a big issue: “Controls defined within a template are not available for manipulation until they are instantiated inside another control.” While analyzing the WeblogPostCommentForm control I found that he uses the ITemplate technique to compose it’s layout and unfortunately I also found that the template content vary from theme to theme. This could have been a problem but luckily WeblogPostCommentForm control template content always contains a submit button with a well known ID (at least I can assume that there are a well known set of IDs). Using this submit button as anchor it’s possible to add the Captcha controls in the correct place. Another important finding was that WeblogPostCommentForm control inherits from the WrappedFormBase control which is the base control for all CommunityServer input forms. Knowing this inheritance link the main goal has changed to became the creation of a base ControlAdapter that could be extended and customized to allow adding Captcha to: post comments form contact form user creation form. And, with this mind set, I decided to used the following ControlAdapter base class signature :public abstract class WrappedFormBaseCaptchaAdapter<T> : ControlAdapter where T : WrappedFormBase { }Great, but there are still many to do … Captcha The Captcha will be assembled with: A dynamically generated image with a set of random numbers A TextBox control where the image number will be inserted A Validator control to validate whether TextBox numbers match the image numbers This is a common Captcha implementation, is not rocket science and don’t bring any additional problem. The main problem, as told before, is to find the correct anchor control to ensure a correct Captcha control injection. The anchor control can vary by: target control theme Implementation To support this dynamic scenario I choose to use the following implementation:private List<string> _validAnchorIds = null; protected virtual List<string> ValidAnchorIds { get { if (this._validAnchorIds == null) { this._validAnchorIds = new List<string>(); this._validAnchorIds.Add("btnSubmit"); } return this._validAnchorIds; } } private Control GetAnchorControl(T wrapper) { if (this.ValidAnchorIds == null || this.ValidAnchorIds.Count == 0) { throw new ArgumentException("Cannot be null or empty", "validAnchorNames"); } var q = from anchorId in this.ValidAnchorIds let anchorControl = CSControlUtility.Instance().FindControl(wrapper, anchorId) where anchorControl != null select anchorControl; return q.FirstOrDefault(); } I can now, using the ValidAnchorIds property, configure a set of valid anchor control Ids. The GetAnchorControl method searches for a valid anchor control within the set of valid control Ids. Here, some of you may question why to use a LINQ To Objects expression, but the important here is to notice the usage of CSControlUtility.Instance().FindControl CommunityServer method. I want to build on top of CommunityServer not to reinvent the wheel. Assuming that an anchor control was found, it’s now possible to inject the Captcha at the correct place. This not something new, we do this all the time when creating server controls or adding dynamic controls:protected sealed override void CreateChildControls() { base.CreateChildControls(); if (this.IsCaptchaRequired) { T wrapper = base.Control as T; if (wrapper != null) { Control anchorControl = GetAnchorControl(wrapper); if (anchorControl != null) { Panel phCaptcha = new Panel {CssClass = "CommonFormField", ID = "Captcha"}; int index = anchorControl.Parent.Controls.IndexOf(anchorControl); anchorControl.Parent.Controls.AddAt(index, phCaptcha); CaptchaConfiguration.DefaultProvider.AddCaptchaControls( phCaptcha, GetValidationGroup(wrapper, anchorControl)); } } } } Here you can see a new entity in action: a provider. This is a CaptchaProvider class instance and is only goal is to create the Captcha itself and do everything else is needed to ensure is correct operation.public abstract class CaptchaProvider : ProviderBase { public abstract void AddCaptchaControls(Panel captchaPanel, string validationGroup); } You can create your own specific CaptchaProvider class to use different Captcha strategies including the use of existing Captcha services like ReCaptcha. Once the generic ControlAdapter was created became extremely easy to created a specific one. Here is the specific ControlAdapter for the WeblogPostCommentForm control:public class WeblogPostCommentFormCaptchaAdapter : WrappedFormBaseCaptchaAdapter<WrappedFormBase> { #region Overriden Methods protected override List<string> ValidAnchorIds { get { List<string> validAnchorNames = base.ValidAnchorIds; validAnchorNames.Add("CommentSubmit"); return validAnchorNames; } } protected override string DefaultValidationGroup { get { return "CreateCommentForm"; } } #endregion Overriden Methods } Configuration This is the magic step. Without changing the original pages and keeping the application original assemblies untouched we are going to add a new behavior to the CommunityServer application. To glue everything together you must follow this steps: Add the following configuration to default.browser file:<?xml version='1.0' encoding='utf-8'?> <browsers> <browser refID="Default"> <controlAdapters>  <adapter controlType="CommunityServer.Blogs.Controls.WeblogPostCommentForm" adapterType="NunoGomes.CommunityServer.Components.WeblogPostCommentFormCaptchaAdapter, NunoGomes.CommunityServer" /> </controlAdapters> </browser> </browsers> Add the following configuration to web.config file:<configuration> <configSections>  <section name="communityServer.Captcha" type="NunoGomes.CommunityServer.Captcha.Configuration.CaptchaSection" /> </configSections>  <communityServer.Captcha defaultProvider="simpleCaptcha"> <providers> <add name="simpleCaptcha" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProvider, NunoGomes.CommunityServer" imageUrl="~/captcha.ashx" enabled="true" passPhrase="_YourPassPhrase_" saltValue="_YourSaltValue_" hashAlgorithm="SHA1" passwordIterations="3" keySize="256" initVector="_YourInitVectorWithExactly_16_Bytes_" /> </providers> </communityServer.Captcha> <system.web> <httpHandlers>  <add verb="GET" path="captcha.ashx" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProviderImageHandler, NunoGomes.CommunityServer" /> </httpHandlers> </system.web> <system.webServer> <handlers accessPolicy="Read, Write, Script, Execute">  <add verb="GET" name="captcha" path="captcha.ashx" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProviderImageHandler, NunoGomes.CommunityServer" /> </handlers> </system.webServer> </configuration> Conclusion Building a ControlAdapter can be complex but the reward is his ability to allows us, thru configuration changes, to modify an application render and/or behavior. You can see this ControlAdapter in action here and here (anonymous required). A complete solution is available in “CommunityServer Extensions” Codeplex project.

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Overwriting TFS Web Services

- by javarg

In this blog I will share a technique I used to intercept TFS Web Services calls. This technique is a very invasive one and requires you to overwrite default TFS Web Services behavior. I only recommend taking such an approach when other means of TFS extensibility fail to provide the same functionality (this is not a supported TFS extensibility point). For instance, intercepting and aborting a Work Item change operation could be implemented using this approach (consider TFS Subscribers functionality before taking this approach, check Martin’s post about subscribers). So let’s get started. The technique consists in versioning TFS Web Services .asmx service classes. If you look into TFS’s ASMX services you will notice that versioning is supported by creating a class hierarchy between different product versions. For instance, let’s take the Work Item management service .asmx. Check the following .asmx file located at: %Program Files%\Microsoft Team Foundation Server 2010\Application Tier\Web Services\_tfs_resources\WorkItemTracking\v3.0\ClientService.asmx The .asmx references the class Microsoft.TeamFoundation.WorkItemTracking.Server.ClientService3: <%-- Copyright (c) Microsoft Corporation. All rights reserved. --%> <%@ webservice language="C#" Class="Microsoft.TeamFoundation.WorkItemTracking.Server.ClientService3" %> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The inheritance hierarchy for this service class follows: Note the naming convention used for service versioning (ClientService3, ClientService2, ClientService). We will need to overwrite the latest service version provided by the product (in this case ClientService3 for TFS 2010). The following example intercepts and analyzes WorkItem fields. Suppose we need to validate state changes with more advanced logic other than the provided validations/constraints of the process template. Important: Backup the original .asmx file and create one of your own. Create a Visual Studio Web App Project and include a new ASMX Web Service in the project Add the following references to the project (check the folder %Program Files%\Microsoft Team Foundation Server 2010\Application Tier\Web Services\bin\): Microsoft.TeamFoundation.Framework.Server.dll Microsoft.TeamFoundation.Server.dll Microsoft.TeamFoundation.Server.dll Microsoft.TeamFoundation.WorkItemTracking.Client.QueryLanguage.dll Microsoft.TeamFoundation.WorkItemTracking.Server.DataAccessLayer.dll Microsoft.TeamFoundation.WorkItemTracking.Server.DataServices.dll Replace the default service implementation with the something similar to the following code: Code Snippet /// <summary> /// Inherit from ClientService3 to overwrite default Implementation /// </summary> [WebService(Namespace = "http://schemas.microsoft.com/TeamFoundation/2005/06/WorkItemTracking/ClientServices/03", Description = "Custom Team Foundation WorkItemTracking ClientService Web Service")] public class CustomTfsClientService : ClientService3 { [WebMethod, SoapHeader("requestHeader", Direction = SoapHeaderDirection.In)] public override bool BulkUpdate( XmlElement package, out XmlElement result, MetadataTableHaveEntry[] metadataHave, out string dbStamp, out Payload metadata) { var xe = XElement.Parse(package.OuterXml); // We only intercept WorkItems Updates (we can easily extend this sample to capture any operation). var wit = xe.Element("UpdateWorkItem"); if (wit != null) { if (wit.Attribute("WorkItemID") != null) { int witId = (int)wit.Attribute("WorkItemID"); // With this Id. I can query TFS for more detailed information, using TFS Client API (assuming the WIT already exists). var stateChanged = wit.Element("Columns").Elements("Column").FirstOrDefault(c => (string)c.Attribute("Column") == "System.State"); if (stateChanged != null) { var newStateName = stateChanged.Element("Value").Value; if (newStateName == "Resolved") { throw new Exception("Cannot change state to Resolved!"); } } } } // Finally, we call base method implementation return base.BulkUpdate(package, out result, metadataHave, out dbStamp, out metadata); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } 4. Build your solution and overwrite the original .asmx with the new implementation referencing our new service version (don’t forget to backup it up first). 5. Copy your project’s .dll into the following path: %Program Files%\Microsoft Team Foundation Server 2010\Application Tier\Web Services\bin 6. Try saving a WorkItem into the Resolved state. Enjoy!

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LLBLGen Pro v3.1 released!

- by FransBouma

Yesterday we released LLBLGen Pro v3.1! Version 3.1 comes with new features and enhancements, which I'll describe briefly below. v3.1 is a free upgrade for v3.x licensees. What's new / changed? Designer Extensible Import system. An extensible import system has been added to the designer to import project data from external sources. Importers are plug-ins which import project meta-data (like entity definitions, mappings and relational model data) from an external source into the loaded project. In v3.1, an importer plug-in for importing project elements from existing LLBLGen Pro v3.x project files has been included. You can use this importer to create source projects from which you import parts of models to build your actual project with. Model-only relationships. In v3.1, relationships of the type 1:1, m:1 and 1:n can be marked as model-only. A model-only relationship isn't required to have a backing foreign key constraint in the relational model data. They're ideal for projects which have to work with relational databases where changes can't always be made or some relationships can't be added to (e.g. the ones which are important for the entity model, but are not allowed to be added to the relational model for some reason). Custom field ordering. Although fields in an entity definition don't really have an ordering, it can be important for some situations to have the entity fields in a given order, e.g. when you use compound primary keys. Field ordering can be defined using a pop-up dialog which can be opened through various ways, e.g. inside the project explorer, model view and entity editor. It can also be set automatically during refreshes based on new settings. Command line relational model data refresher tool, CliRefresher.exe. The command line refresh tool shipped with v2.6 is now available for v3.1 as well Navigation enhancements in various designer elements. It's now easier to find elements like entities, typed views etc. in the project explorer from editors, to navigate to related entities in the project explorer by right clicking a relationship, navigate to the super-type in the project explorer when right-clicking an entity and navigate to the sub-type in the project explorer when right-clicking a sub-type node in the project explorer. Minor visual enhancements / tweaks LLBLGen Pro Runtime Framework Entity creation is now up to 30% faster and takes 5% less memory. Creating an entity object has been optimized further by tweaks inside the framework to make instantiating an entity object up to 30% faster. It now also takes up to 5% less memory than in v3.0 Prefetch Path node merging is now up to 20-25% faster. Setting entity references required the creation of a new relationship object. As this relationship object is always used internally it could be cached (as it's used for syncing only). This increases performance by 20-25% in the merging functionality. Entity fetches are now up to 20% faster. A large number of tweaks have been applied to make entity fetches up to 20% faster than in v3.0. Full WCF RIA support. It's now possible to use your LLBLGen Pro runtime framework powered domain layer in a WCF RIA application using the VS.NET tools for WCF RIA services. WCF RIA services is a Microsoft technology for .NET 4 and typically used within silverlight applications. SQL Server DQE compatibility level is now per instance. (Usable in Adapter). It's now possible to set the compatibility level of the SQL Server Dynamic Query Engine (DQE) per instance of the DQE instead of the global setting it was before. The global setting is still available and is used as the default value for the compatibility level per-instance. You can use this to switch between CE Desktop and normal SQL Server compatibility per DataAccessAdapter instance. Support for COUNT_BIG aggregate function (SQL Server specific). The aggregate function COUNT_BIG has been added to the list of available aggregate functions to be used in the framework. Minor changes / tweaks I'm especially pleased with the import system, as that makes working with entity models a lot easier. The import system lets you import from another LLBLGen Pro v3 project any entity definition, mapping and / or meta-data like table definitions. This way you can build repository projects where you store model fragments, e.g. the building blocks for a customer-order system, a user credential model etc., any model you can think of. In most projects, you'll recognize that some parts of your new model look familiar. In these cases it would have been easier if you would have been able to import these parts from projects you had pre-created. With LLBLGen Pro v3.1 you can. For example, say you have an Oracle schema called CRM which contains the bread 'n' butter customer-order-product kind of model. You create an entity model from that schema and save it in a project file. Now you start working on another project for another customer and you have to use SQL Server. You also start using model-first development, so develop the entity model from scratch as there's no existing database. As this customer also requires some CRM like entity model, you import the entities from your saved Oracle project into this new SQL Server targeting project. Because you don't work with Oracle this time, you don't import the relational meta-data, just the entities, their relationships and possibly their inheritance hierarchies, if any. As they're now entities in your project you can change them a bit to match the new customer's requirements. This can save you a lot of time, because you can re-use pre-fab model fragments for new projects. In the example above there are no tables yet (as you work model first) so using the forward mapping capabilities of LLBLGen Pro v3 creates the tables, PK constraints, Unique Constraints and FK constraints for you. This way you can build a nice repository of model fragments which you can re-use in new projects.

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Code excavations, wishful invocations, perimeters and domain specific unit test frameworks

- by RoyOsherove

One of the talks I did at QCON London was about a subject that I’ve come across fairly recently , when I was building SilverUnit – a “pure” unit test framework for silverlight objects that depend on the silverlight runtime to run. It is the concept of “cogs in the machine” – when your piece of code needs to run inside a host framework or runtime that you have little or no control over for testability related matters. Examples of such cogs and machines can be: your custom control running inside silverlight runtime in the browser your plug-in running inside an IDE your activity running inside a windows workflow your code running inside a java EE bean your code inheriting from a COM+ (enterprise services) component etc.. Not all of these are necessarily testability problems. The main testability problem usually comes when your code actually inherits form something inside the system. For example. one of the biggest problems with testing objects like silverlight controls is the way they depend on the silverlight runtime – they don’t implement some silverlight interface, they don’t just call external static methods against the framework runtime that surrounds them – they actually inherit parts of the framework: they all inherit (in this case) from the silverlight DependencyObject Wrapping it up? An inheritance dependency is uniquely challenging to bring under test, because “classic” methods such as wrapping the object under test with a framework wrapper will not work, and the only way to do manually is to create parallel testable objects that get delegated with all the possible actions from the dependencies. In silverlight’s case, that would mean creating your own custom logic class that would be called directly from controls that inherit from silverlight, and would be tested independently of these controls. The pro side is that you get the benefit of understanding the “contract” and the “roles” your system plays against your logic, but unfortunately, more often than not, it can be very tedious to create, and may sometimes feel unnecessary or like code duplication. About perimeters A perimeter is that invisible line that your draw around your pieces of logic during a test, that separate the code under test from any dependencies that it uses. Most of the time, a test perimeter around an object will be the list of seams (dependencies that can be replaced such as interfaces, virtual methods etc.) that are actually replaced for that test or for all the tests. Role based perimeters In the case of creating a wrapper around an object – one really creates a “role based” perimeter around the logic that is being tested – that wrapper takes on roles that are required by the code under test, and also communicates with the host system to implement those roles and provide any inputs to the logic under test. in the image below – we have the code we want to test represented as a star. No perimeter is drawn yet (we haven’t wrapped it up in anything yet). in the image below is what happens when you wrap your logic with a role based wrapper – you get a role based perimeter anywhere your code interacts with the system: There’s another way to bring that code under test – using isolation frameworks like typemock, rhino mocks and MOQ (but if your code inherits from the system, Typemock might be the only way to isolate the code from the system interaction. Ad-Hoc Isolation perimeters the image below shows what I call ad-hoc perimeter that might be vastly different between different tests: This perimeter’s surface is much smaller, because for that specific test, that is all the “change” that is required to the host system behavior. The third way of isolating the code from the host system is the main “meat” of this post: Subterranean perimeters Subterranean perimeters are Deep rooted perimeters - “always on” seams that that can lie very deep in the heart of the host system where they are fully invisible even to the test itself, not just to the code under test. Because they lie deep inside a system you can’t control, the only way I’ve found to control them is with runtime (not compile time) interception of method calls on the system. One way to get such abilities is by using Aspect oriented frameworks – for example, in SilverUnit, I’ve used the CThru AOP framework based on Typemock hooks and CLR profilers to intercept such system level method calls and effectively turn them into seams that lie deep down at the heart of the silverlight runtime. the image below depicts an example of what such a perimeter could look like: As you can see, the actual seams can be very far away form the actual code under test, and as you’ll discover, that’s actually a very good thing. Here is only a partial list of examples of such deep rooted seams : disabling the constructor of a base class five levels below the code under test (this.base.base.base.base) faking static methods of a type that’s being called several levels down the stack: method x() calls y() calls z() calls SomeType.StaticMethod() Replacing an async mechanism with a synchronous one (replacing all timers with your own timer behavior that always Ticks immediately upon calls to “start()” on the same caller thread for example) Replacing event mechanisms with your own event mechanism (to allow “firing” system events) Changing the way the system saves information with your own saving behavior (in silverunit, I replaced all Dependency Property set and get with calls to an in memory value store instead of using the one built into silverlight which threw exceptions without a browser) several questions could jump in: How do you know what to fake? (how do you discover the perimeter?) How do you fake it? Wouldn’t this be problematic - to fake something you don’t own? it might change in the future How do you discover the perimeter to fake? To discover a perimeter all you have to do is start with a wishful invocation. a wishful invocation is the act of trying to invoke a method (or even just create an instance ) of an object using “regular” test code. You invoke the thing that you’d like to do in a real unit test, to see what happens: Can I even create an instance of this object without getting an exception? Can I invoke this method on that instance without getting an exception? Can I verify that some call into the system happened? You make the invocation, get an exception (because there is a dependency) and look at the stack trace. choose a location in the stack trace and disable it. Then try the invocation again. if you don’t get an exception the perimeter is good for that invocation, so you can move to trying out other methods on that object. in a future post I will show the process using CThru, and how you end up with something close to a domain specific test framework after you’re done creating the perimeter you need.

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LLBLGen Pro feature highlights: grouping model elements

- by FransBouma

(This post is part of a series of posts about features of the LLBLGen Pro system) When working with an entity model which has more than a few entities, it's often convenient to be able to group entities together if they belong to a semantic sub-model. For example, if your entity model has several entities which are about 'security', it would be practical to group them together under the 'security' moniker. This way, you could easily find them back, yet they can be left inside the complete entity model altogether so their relationships with entities outside the group are kept. In other situations your domain consists of semi-separate entity models which all target tables/views which are located in the same database. It then might be convenient to have a single project to manage the complete target database, yet have the entity models separate of each other and have them result in separate code bases. LLBLGen Pro can do both for you. This blog post will illustrate both situations. The feature is called group usage and is controllable through the project settings. This setting is supported on all supported O/R mapper frameworks. Situation one: grouping entities in a single model. This situation is common for entity models which are dense, so many relationships exist between all sub-models: you can't split them up easily into separate models (nor do you likely want to), however it's convenient to have them grouped together into groups inside the entity model at the project level. A typical example for this is the AdventureWorks example database for SQL Server. This database, which is a single catalog, has for each sub-group a schema, however most of these schemas are tightly connected with each other: adding all schemas together will give a model with entities which indirectly are related to all other entities. LLBLGen Pro's default setting for group usage is AsVisualGroupingMechanism which is what this situation is all about: we group the elements for visual purposes, it has no real meaning for the model nor the code generated. Let's reverse engineer AdventureWorks to an entity model. By default, LLBLGen Pro uses the target schema an element is in which is being reverse engineered, as the group it will be in. This is convenient if you already have categorized tables/views in schemas, like which is the case in AdventureWorks. Of course this can be switched off, or corrected on the fly. When reverse engineering, we'll walk through a wizard which will guide us with the selection of the elements which relational model data should be retrieved, which we can later on use to reverse engineer to an entity model. The first step after specifying which database server connect to is to select these elements. below we can see the AdventureWorks catalog as well as the different schemas it contains. We'll include all of them. After the wizard completes, we have all relational model data nicely in our catalog data, with schemas. So let's reverse engineer entities from the tables in these schemas. We select in the catalog explorer the schemas 'HumanResources', 'Person', 'Production', 'Purchasing' and 'Sales', then right-click one of them and from the context menu, we select Reverse engineer Tables to Entity Definitions.... This will bring up the dialog below. We check all checkboxes in one go by checking the checkbox at the top to mark them all to be added to the project. As you can see LLBLGen Pro has already filled in the group name based on the schema name, as this is the default and we didn't change the setting. If you want, you can select multiple rows at once and set the group name to something else using the controls on the dialog. We're fine with the group names chosen so we'll simply click Add to Project. This gives the following result: (I collapsed the other groups to keep the picture small ;)). As you can see, the entities are now grouped. Just to see how dense this model is, I've expanded the relationships of Employee: As you can see, it has relationships with entities from three other groups than HumanResources. It's not doable to cut up this project into sub-models without duplicating the Employee entity in all those groups, so this model is better suited to be used as a single model resulting in a single code base, however it benefits greatly from having its entities grouped into separate groups at the project level, to make work done on the model easier. Now let's look at another situation, namely where we work with a single database while we want to have multiple models and for each model a separate code base. Situation two: grouping entities in separate models within the same project. To get rid of the entities to see the second situation in action, simply undo the reverse engineering action in the project. We still have the AdventureWorks relational model data in the catalog. To switch LLBLGen Pro to see each group in the project as a separate project, open the Project Settings, navigate to General and set Group usage to AsSeparateProjects. In the catalog explorer, select Person and Production, right-click them and select again Reverse engineer Tables to Entities.... Again check the checkbox at the top to mark all entities to be added and click Add to Project. We get two groups, as expected, however this time the groups are seen as separate projects. This means that the validation logic inside LLBLGen Pro will see it as an error if there's e.g. a relationship or an inheritance edge linking two groups together, as that would lead to a cyclic reference in the code bases. To see this variant of the grouping feature, seeing the groups as separate projects, in action, we'll generate code from the project with the two groups we just created: select from the main menu: Project -> Generate Source-code... (or press F7 ;)). In the dialog popping up, select the target .NET framework you want to use, the template preset, fill in a destination folder and click Start Generator (normal). This will start the code generator process. As expected the code generator has simply generated two code bases, one for Person and one for Production: The group name is used inside the namespace for the different elements. This allows you to add both code bases to a single solution and use them together in a different project without problems. Below is a snippet from the code file of a generated entity class. //... using System.Xml.Serialization; using AdventureWorks.Person; using AdventureWorks.Person.HelperClasses; using AdventureWorks.Person.FactoryClasses; using AdventureWorks.Person.RelationClasses; using SD.LLBLGen.Pro.ORMSupportClasses; namespace AdventureWorks.Person.EntityClasses { //... /// <summary>Entity class which represents the entity 'Address'.<br/><br/></summary> [Serializable] public partial class AddressEntity : CommonEntityBase //... The advantage of this is that you can have two code bases and work with them separately, yet have a single target database and maintain everything in a single location. If you decide to move to a single code base, you can do so with a change of one setting. It's also useful if you want to keep the groups as separate models (and code bases) yet want to add relationships to elements from another group using a copy of the entity: you can simply reverse engineer the target table to a new entity into a different group, effectively making a copy of the entity. As there's a single target database, changes made to that database are reflected in both models which makes maintenance easier than when you'd have a separate project for each group, with its own relational model data. Conclusion LLBLGen Pro offers a flexible way to work with entities in sub-models and control how the sub-models end up in the generated code.

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Dynamic Code for type casting Generic Types 'generically' in C#

- by Rick Strahl

C# is a strongly typed language and while that's a fundamental feature of the language there are more and more situations where dynamic types make a lot of sense. I've written quite a bit about how I use dynamic for creating new type extensions: Dynamic Types and DynamicObject References in C# Creating a dynamic, extensible C# Expando Object Creating a dynamic DataReader for dynamic Property Access Today I want to point out an example of a much simpler usage for dynamic that I use occasionally to get around potential static typing issues in C# code especially those concerning generic types. TypeCasting Generics Generic types have been around since .NET 2.0 I've run into a number of situations in the past - especially with generic types that don't implement specific interfaces that can be cast to - where I've been unable to properly cast an object when it's passed to a method or assigned to a property. Granted often this can be a sign of bad design, but in at least some situations the code that needs to be integrated is not under my control so I have to make due with what's available or the parent object is too complex or intermingled to be easily refactored to a new usage scenario. Here's an example that I ran into in my own RazorHosting library - so I have really no excuse, but I also don't see another clean way around it in this case. A Generic Example Imagine I've implemented a generic type like this: public class RazorEngine<TBaseTemplateType> where TBaseTemplateType : RazorTemplateBase, new() You can now happily instantiate new generic versions of this type with custom template bases or even a non-generic version which is implemented like this: public class RazorEngine : RazorEngine<RazorTemplateBase> { public RazorEngine() : base() { } } To instantiate one: var engine = new RazorEngine<MyCustomRazorTemplate>(); Now imagine that the template class receives a reference to the engine when it's instantiated. This code is fired as part of the Engine pipeline when it gets ready to execute the template. It instantiates the template and assigns itself to the template: var template = new TBaseTemplateType() { Engine = this } The problem here is that possibly many variations of RazorEngine<T> can be passed. I can have RazorTemplateBase, RazorFolderHostTemplateBase, CustomRazorTemplateBase etc. as generic parameters and the Engine property has to reflect that somehow. So, how would I cast that? My first inclination was to use an interface on the engine class and then cast to the interface. Generally that works, but unfortunately here the engine class is generic and has a few members that require the template type in the member signatures. So while I certainly can implement an interface: public interface IRazorEngine<TBaseTemplateType> it doesn't really help for passing this generically templated object to the template class - I still can't cast it if multiple differently typed versions of the generic type could be passed. I have the exact same issue in that I can't specify a 'generic' generic parameter, since there's no underlying base type that's common. In light of this I decided on using object and the following syntax for the property (and the same would be true for a method parameter): public class RazorTemplateBase :MarshalByRefObject,IDisposable { public object Engine {get;set; } } Now because the Engine property is a non-typed object, when I need to do something with this value, I still have no way to cast it explicitly. What I really would need is: public RazorEngine<> Engine { get; set; } but that's not possible. Dynamic to the Rescue Luckily with the dynamic type this sort of thing can be mitigated fairly easily. For example here's a method that uses the Engine property and uses the well known class interface by simply casting the plain object reference to dynamic and then firing away on the properties and methods of the base template class that are common to all templates:/// <summary> /// Allows rendering a dynamic template from a string template /// passing in a model. This is like rendering a partial /// but providing the input as a /// </summary> public virtual string RenderTemplate(string template,object model) { if (template == null) return string.Empty; // if there's no template markup if(!template.Contains("@")) return template; // use dynamic to get around generic type casting dynamic engine = Engine; string result = engine.RenderTemplate(template, model); if (result == null) throw new ApplicationException("RenderTemplate failed: " + engine.ErrorMessage); return result; } Prior to .NET 4.0 I would have had to use Reflection for this sort of thing which would have a been a heck of a lot more verbose, but dynamic makes this so much easier and cleaner and in this case at least the overhead is negliable since it's a single dynamic operation on an otherwise very complex operation call. Dynamic as a Bailout Sometimes this sort of thing often reeks of a design flaw, and I agree that in hindsight this could have been designed differently. But as is often the case this particular scenario wasn't planned for originally and removing the generic signatures from the base type would break a ton of other code in the framework. Given the existing fairly complex engine design, refactoring an interface to remove generic types just to make this particular code work would have been overkill. Instead dynamic provides a nice and simple and relatively clean solution. Now if there were many other places where this occurs I would probably consider reworking the code to make this cleaner but given this isolated instance and relatively low profile operation use of dynamic seems a valid choice for me. This solution really works anywhere where you might end up with an inheritance structure that doesn't have a common base or interface that is sufficient. In the example above I know what I'm getting but there's no common base type that I can cast to. All that said, it's a good idea to think about use of dynamic before you rush in. In many situations there are alternatives that can still work with static typing. Dynamic definitely has some overhead compared to direct static access of objects, so if possible we should definitely stick to static typing. In the example above the application already uses dynamics extensively for dynamic page page templating and passing models around so introducing dynamics here has very little additional overhead. The operation itself also fires of a fairly resource heavy operation where the overhead of a couple of dynamic member accesses are not a performance issue. So, what's your experience with dynamic as a bailout mechanism? © Rick Strahl, West Wind Technologies, 2005-2012Posted in CSharp Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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CodePlex Daily Summary for Thursday, April 15, 2010

CodePlex Daily Summary for Thursday, April 15, 2010New ProjectsApplication Logging Repository (ALR): The ALR is a light-weight logging framework that allows applications to log events and exceptions to a central repository.Arkane.FileProperties.DSS: Arkane.FileProperties.Dss is a library for parsing the file header of a .DSS file (as used by Olympus digital dictaphone systems) to obtain time, v...B in conTrol project: This project enables controling log-in and locking your workstation automatically, identifyng you bluetooth.DarkBook: DarkBook is a personal library project.Direct2D for Microsoft .Net: Direct2D, DirectWrite and Windows Imaging wrappers for .Net. This library allows to access Direct2D, DirectWrite and Windows Imaging Windows API f...DJ Ware: DJ Ware is an extensible music player with plugin support and innovative features to organize and explore music files. It is developed with C#, WPF...gpsMe: gpsMe is a Windows Mobile 6.x mapping solution allowing to place the user on a personnalized map. The screen requirements are VGA or WVGA but, you ...jErrorLog: jErrorLog is an error logging component for use in DotNet 2.0 or later applications. It can log error messages to any of the following: database, e...KEMET_API: Java Library (open - source). This library is a help to study egyptian hieroglyphs.Meadow: A web site project for a Swedish floorball team called Slackers. Home page built with ASP.NET 2.0, ASP.NET AJAX and SQL Server 2005.Mustang Math: Mustang Math makes it easier for young children to practice basic math facts on the computer. No keyboard or mouse required - just say the answer!...Net.Formats.oEmbed: oEmbed format implementation in c#. oEmbed is a format for allowing an embedded representation of a URL on third party sites. The simple API allows...Normlize O/R Mapper: Open source O/RM tool that participates with traditional inheritance object models as well as Hibernate/nHibernate style class shells. As I have t...N-Twill Twitter Client for VB.NET: Proyecto de cliente twitter hecho con la libreria TwitterVB2 y hecho en VB.net 2008.SIQM: Spatial Information Quality Management Toolset TIMETABLEASY Web: Under developmentTweetSharp: TweetSharp is a complete .NET library for micro-blogging platforms that allows you to write short and sweet expressions that fly to Twitter, Yammer...UISandbox: UISandbox is a sample C# source code showing how to deal with plugins requiring sandbox, when those plugins must interact with WPF application inte...WinForm SharePoint Web Part Manager: The SharePoint Web Part Manager is a WinForm tool using the SharePoint object model that enables developers and power users to add, update, delete,...WoW Character Viewer: View your World of Warcraft character (or anyone else's character), using this application. Written using Visual Basic Express 2008, then ported t...Xrns2XMod: Xrns2XMod converts from Renoise format (xrns) to mod or xm, which are more compatible formats playable from xmplay or vlc.New ReleasesArkane.FileProperties.DSS: 1.0 stable release: Executables and merge module for 1.0. (See documentation.)Bluetooth Radar: Version 2.0: Add IrDA reference for Bluetooth sending using Obex Add Project icon Add Bluetooth detection mode (Auto close application is there is no blueto...BUtil: BUtil 5.0 Alpha: Backup tasks adding.... in progressChronos WPF: Chronos v1.0 RC 1: Chronos v1.0 RC 1. Development will be feature frozen after this release, only bug fixes will be allowed. Updated nRoute assembly to v0.4 (http:...clipShow: Version 2.5: Release that addresses the canonical syntax issues in search discoverd by Tschachim (thanks again!). Also, the play list and play all menu items s...DarkBook: DarkBook alpha: Hi, here comes the alpha version of Darkbook. It has all the functions already but is still in developing. I hope it's helpful for you, at least it...DirectQ: Release 1.8.3a: Improvements to 1.8.2, which will be shortly be removed. This replaces the original 1.8.3 release from earlier today which had some late-breaking ...Effect Custom Tool for Visual Studio: Effect Custom Tool v1.1: Effect Custom Tool for Visual Studio is a visual studio 2008 extension that helps you generate c# classes from effect (*.fx) files for use with Xna...Folder Bookmarks: Folder Bookmarks 1.4.3: This is the latest version of Folder Bookmarks (1.4.3), with general improvements. It has an installer - it will create a directory 'CPascoe' in My...gpsMe: gpsMe v0.3: Required Hardware Windows Mobile 6 .Net Compact Framework 3.5 integrated gps device VGA or WVGA screen (normally works on others)IST435: Lab 4 - Enterprise Level CMS with DotNetNuke: Lab 4 - Enterprise Level CMS with DotNetNukeThis is the "starter kit" that you must base your Lab 4 on. This lab must be completed in-class.Mouse Jiggler: MouseJiggle-1.1: 1.1 release of Mouse Jiggler, now with x64 compatibility and the ability to start jiggling on run with the --jiggle or -j command-line switch.Mustang Math: MustangMath.exe: This is a quick and dirty "0.1" prototype to demonstrate the speech recognition idea. It starts asking you questions automatically on launch and k...MvcContrib: a Codeplex Foundation project: 2.0.36.0 for MVC2 (RTW): Please see the Change Log for a complete list of changes. MVC BootCamp Description of the releases: MvcContrib.Release.zip MvcContrib.dll MvcC...Nito.LINQ: Beta (v0.3): New features for this release: Several new supported platforms (see below). PDBs that are source-indexed to the appropriate CodePlex changeset. ...OpenIdPortableArea: 0.1.0.2 OpenIdPortableArea: OpenIdPortableArea.Release: DotNetOpenAuth.dll DotNetOpenAuth.xml MvcContrib.dll MvcContrib.xml OpenIdPortableArea.dll OpenIdPortableAre...PokeIn Comet Ajax Library: PokeIn Sample with Library v0.2: New version of PokeIn library with sample. v0.2 There are new features in this release and no bug detected yet.Project Tru Tiên: Elements-test V1-fix (v2): Là EL test được fix tiếp theo bản fix V1, tạm gọi đây là bản fix V2 của ELtest Trong bản fix này EL được fix thêm vụ Quest, Quest chỉnh sửa đúng t...Rule 18 - Love your clipboard: Rule 18: This is the third public beta for the first version of Rule 18. This version has been updated to support Visual Studio 2010 RTM and .NET 4.0 RTM. ...SevenZipSharp: SevenZipSharp 0.62: Added: Extraction from SFX archives. Now it is possible to unrar RAR self-extractors, unzip ZIP self-extractors, etc. Extraction from DOC, XLS, (...SharePoint Labs: SPLab3001A-FRA-Level200: SPLab3001A-FRA-Level200 This SharePoint Lab will teach the persistence object layer that SharePoint uses to centraly store configuration data and o...TTXPathNavigator: TTXPathNavigator for VS2010: Version for Visual Studio 2010turing machine simulator: SDS: SDS documentVecDraw: VecDraw_0.2.25: Alpha release for test purposesWinForm SharePoint Web Part Manager: Beta 1: First release of the WinForm SharePoitn web part manager toolXrns2XMod: Xrns2XMod 0.5.1: Mod and XM conversion format - No sample data conversion at momentZip Solution: ZipSolution 5.3: Features: 1. Added WaitMsec for visual studio support with getting access to files in post build event; 2. Added ShowTextInToolbars to app.config ...Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesPHPExcelpatterns & practices – Enterprise LibraryMost Active ProjectsRawrpatterns & practices – Enterprise LibraryGMap.NET - Great Maps for Windows Forms & PresentationFarseer Physics EngineIonics Isapi Rewrite FilterNB_Store - Free DotNetNuke Ecommerce Catalog ModuleBlogEngine.NETjQuery Library for SharePoint Web ServicesDotRasFacebook Developer Toolkit

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SharePoint Upgrade Global Nav Quirks?

- by elorg

We're working on a parallel install/upgrade of SharePoint. The client has WSS 2003 on some old hardware. We've installed MOSS 2007 in a medium farm environment. They want to use this as an opportunity to not just upgrade and use the new features, but to also better organize their content and categorize between different site collections. To accommodate, we've created a few site collections per their specifications in the new environment, and when we ran an upgrade test run we ran into a few .. quirks. We made a backup of the old content database, copied it over to the new environment and restored it as a new database. Created a new web app and attached the migrated data to do an in-place upgrade in this new "test" area. This seems pretty standard - no issues. We have to do a little bit of cleanup (e.g. reset pages to site definition, reset themes, and inherit the global nav / top link bar, etc.). Once that's done, we're using stsadm export/import to copy the individual sites over to their ultimate destinations in the various different site collections. So far so good. But then we ran into one particular site that has a link to an .aspx page in the top link bar in WSS 2003 that's not behaving properly after the upgrade. It's just a link to a "dashboard" .aspx page in a doc library - nothing special. It doesn't seem to matter what we do, or what order we do it (in the "test" web app, in the destination web app, or both). In the end, this ONE site will not allow us to create a link/tab in the global nav. It can inherit the global nav just fine. We can break the inheritance just fine. But if we want to manually add a link in the top link bar - we go through the steps that I've done 1,000x before and click OK - and the tab never appears. It doesn't matter if it's to a page within the site itself, or to Google. We can migrate over other sites into the same site collection and add a tab without issue. If we migrate this quirky site over to another site collection we run into the same issue. Yet, in the "test" web app that we're using to upgrade the data we can add a tab? If we add the tab before we export/import to the final destination, the tab is lost during the process? Has anyone run into anything like this? Any ideas? I've tried every combination of everything that I can think of and nothing works. Unless we can figure out how to get this to work, we're going to just add this tab to the global nav for the entire site collection and inherit it for this site (but that adds the link to all of the site that will inherit, which is both a pro & con for them).

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ASP.NET WebAPI Security 3: Extensible Authentication Framework

- by Your DisplayName here!

In my last post, I described the identity architecture of ASP.NET Web API. The short version was, that Web API (beta 1) does not really have an authentication system on its own, but inherits the client security context from its host. This is fine in many situations (e.g. AJAX style callbacks with an already established logon session). But there are many cases where you don’t use the containing web application for authentication, but need to do it yourself. Examples of that would be token based authentication and clients that don’t run in the context of the web application (e.g. desktop clients / mobile). Since Web API provides a nice extensibility model, it is easy to implement whatever security framework you want on top of it. My design goals were: Easy to use. Extensible. Claims-based. ..and of course, this should always behave the same, regardless of the hosting environment. In the rest of the post I am outlining some of the bits and pieces, So you know what you are dealing with, in case you want to try the code. At the very heart… is a so called message handler. This is a Web API extensibility point that gets to see (and modify if needed) all incoming and outgoing requests. Handlers run after the conversion from host to Web API, which means that handler code deals with HttpRequestMessage and HttpResponseMessage. See Pedro’s post for more information on the processing pipeline. This handler requires a configuration object for initialization. Currently this is very simple, it contains: Settings for the various authentication and credential types Settings for claims transformation Ability to block identity inheritance from host The most important part here is the credential type support, but I will come back to that later. The logic of the message handler is simple: Look at the incoming request. If the request contains an authorization header, try to authenticate the client. If this is successful, create a claims principal and populate the usual places. If not, return a 401 status code and set the Www-Authenticate header. Look at outgoing response, if the status code is 401, set the Www-Authenticate header. Credential type support Under the covers I use the WIF security token handler infrastructure to validate credentials and to turn security tokens into claims. The idea is simple: an authorization header consists of two pieces: the schema and the actual “token”. My configuration object allows to associate a security token handler with a scheme. This way you only need to implement support for a specific credential type, and map that to the incoming scheme value. The current version supports HTTP Basic Authentication as well as SAML and SWT tokens. (I needed to do some surgery on the standard security token handlers, since WIF does not directly support string-ified tokens. The next version of .NET will fix that, and the code should become simpler then). You can e.g. use this code to hook up a username/password handler to the Basic scheme (the default scheme name for Basic Authentication). config.Handler.AddBasicAuthenticationHandler( (username, password) => username == password); You simply have to provide a password validation function which could of course point back to your existing password library or e.g. membership. The following code maps a token handler for Simple Web Tokens (SWT) to the Bearer scheme (the currently favoured scheme name for OAuth2). You simply have to specify the issuer name, realm and shared signature key: config.Handler.AddSimpleWebTokenHandler( "Bearer", http://identity.thinktecture.com/trust, Constants.Realm, "Dc9Mpi3jaaaUpBQpa/4R7XtUsa3D/ALSjTVvK8IUZbg="); For certain integration scenarios it is very useful if your Web API can consume SAML tokens. This is also easily accomplishable. The following code uses the standard WIF API to configure the usual SAMLisms like issuer, audience, service certificate and certificate validation. Both SAML 1.1 and 2.0 are supported. var registry = new ConfigurationBasedIssuerNameRegistry(); registry.AddTrustedIssuer( "d1 c5 b1 25 97 d0 36 94 65 1c e2 64 fe 48 06 01 35 f7 bd db", "ADFS"); var adfsConfig = new SecurityTokenHandlerConfiguration(); adfsConfig.AudienceRestriction.AllowedAudienceUris.Add( new Uri(Constants.Realm)); adfsConfig.IssuerNameRegistry = registry; adfsConfig.CertificateValidator = X509CertificateValidator.None; // token decryption (read from configuration section) adfsConfig.ServiceTokenResolver = FederatedAuthentication.ServiceConfiguration.CreateAggregateTokenResolver(); config.Handler.AddSaml11SecurityTokenHandler("SAML", adfsConfig); Claims Transformation After successful authentication, if configured, the standard WIF ClaimsAuthenticationManager is called to run claims transformation and validation logic. This stage is used to transform the “technical” claims from the security token into application claims. You can either have a separate transformation logic, or share on e.g. with the containing web application. That’s just a matter of configuration. Adding the authentication handler to a Web API application In the spirit of Web API this is done in code, e.g. global.asax for web hosting: protected void Application_Start() { AreaRegistration.RegisterAllAreas(); ConfigureApis(GlobalConfiguration.Configuration); RegisterGlobalFilters(GlobalFilters.Filters); RegisterRoutes(RouteTable.Routes); BundleTable.Bundles.RegisterTemplateBundles(); } private void ConfigureApis(HttpConfiguration configuration) { configuration.MessageHandlers.Add( new AuthenticationHandler(ConfigureAuthentication())); } private AuthenticationConfiguration ConfigureAuthentication() { var config = new AuthenticationConfiguration { // sample claims transformation for consultants sample, comment out to see raw claims ClaimsAuthenticationManager = new ApiClaimsTransformer(), // value of the www-authenticate header, // if not set, the first scheme added to the handler collection is used DefaultAuthenticationScheme = "Basic" }; // add token handlers - see above return config; } You can find the full source code and some samples here. In the next post I will describe some of the samples in the download, and then move on to authorization. HTH

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Google Analytics on Android

- by pjv

There is a specific and official analytics SDK for native Android apps (note that I'm not talking about webpages in apps on a phone). This library basically sends pages and events to Google Analytics and you can view your analytics in exactly the same dashboard as for websites. Since my background is apps rather than websites, and since a lot of the Google Analytics terminology seems particularly inapplicable to a native app, I need some pointers. Please discuss my remarks, provide some clarification where you think I'm off-track, and above all share good experiences! 1. Page Views Pages mostly can match different Activities (and Dialogs) being displayed. Activities can be visible behind non-full-screen Activities however, though only the top-level Activity can be interacted. This sort-off clashes with a "(page) view". You'd also want at least one page view for each visit and therefore put one page view tracker in the Application class. However this does not constitute a window or sorts. Usually an Activity will open at the same time, so the time spent on that page will have been 0. This will influence your "time spent" statistics. How are these counted anyway? Moreover, there is a loose coupling between the Activities, by means of Intents. A user can, much like on any website, step in at any Activity, although usually this then concerns resuming the application where he left off. This makes that the hierarchy of Activities usually is very flat. And since there are no url's involved. What meaning would using slashes in page titles have, such as "/Home"? All pages would appear on an equal level in the reports, so no content drilldown. Non-unique page views seem to be counted as some kind of indicator of successfulness: how often does the visitor revisit the page. When the user rotates the screen however usually an Activity resumes again, thus making it a new page view. This happens a lot. Maybe a well-thought-through placement of the call might solve this, or placing several, I'm not sure. How to deal with Page Views? 2. Events I'd say there are two sorts: A user event Something that happened, usually as an indirect consequence of the above. The latter particularly is giving me headaches. First of all, many events aren't written in code any more, but pieced logically together by means of Intents. This means that there is no place to put the analytics call. You'd either have to give up this advantage and start doing it the old-fashioned way in favor of good analytics, or, just be missing some events. Secondly, as a developer you're not so much interested in when a user clicks a button, but if the action that should have been performed really was performed and what the result was. There seems to be no clear way to get resulting data into Google Analytics (what's up with the integers? I want to put in Strings!). The same that applies to the flat pages hierarchy, also goes for the event categories. You could do "vertical" categories (topically, that is), but some code is shared "horizontally" and the tracking will be equally shared. Just as with the Intents mechanism, inheritance makes it hard for you to put the tracking in the right places at all times. And I can't really imagine "horizontal" categories. Unless you start making really small categories, such as all the items form the same menu in one category, I have a hard time grasping the concept. Finally, how do you deal with cancelling? Usually you both have an explicit cancel mechanism by ways of a button, as well as the implicit cancel when the "back"-button is pressed to leave the activity and there were no changes. The latter also applies to "saves", when the back button is pressed and there ARE changes. How are you consequently going to catch all these if not by doing all the "back"-button work yourself? How to deal with events? 3. Goals For goal types I have choice of: URL Destination, Time on Site, and Pages/Visit. Most apps don't have a funnel that leads the user to some "registration done" or "order placed" page. Apps have either already been bought (in which case you want to stimulate the user to love your app, so that he might bring on new buyers) or are paid for by in-app ads. So URL Destination is not a very important goal. Time on Site also seems troublesome. First, I have some doubt on how this would be measured. Second, I don't necessarily want my user to spend a lot of time in my already paid app, just be active and content. Equivalently, why not mention how frequent a user uses your app? Regarding Pages/Visit I already mentioned how screen orientation changes blow up the page view numbers. In an app I'd be most interested in events/visit to measure the user's involvement/activity. If he's intensively using the app then he must be loving it right? Furthermore, I also have some small funnels (that do not lead to conversion though) that I want to see streamlined. In my mind those funnels would end in events rather than page views but that seems not to be possible. I could also measure clickthroughs on in-app ads, but then I'd need to track those as Page Views rather than Events, in view of "URL Destination". What are smart goals for apps and how can you fit them on top of Analytics? 4. Optimisation Is there a smart way to manually do what "Website Optimiser" does for websites? Most importantly, how would I track different landing page designs? 5. Traffic Sources Referrals deal with installation time referrals, if you're smart enough to get them included. But perhaps I'd also want to get some data which third-party app sends users to my app to perform some actions (this app interoperability is possible via Intents). Many of the terminologies related to "Traffic Sources" seem totally meaningless and there is no possibility of connecting in AdSense. What are smart uses of this data? 6. Visitors Of the "Browser capabilities", "Network Properties" and "Mobile" tabs, many things are pointless as they have no influence on / relation with my mostly offline app that won't use flash anyway. Only if you drill down far enough, can you get to OS versions, which do matter a lot. I even forgot where you could check what exact Android devices visited. What are smart uses of this data? How can you make the relevant info more prominent? 7. Other No in-page analytics. I have to register my app as a web-url (What!?)?

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ANTS CLR and Memory Profiler In Depth Review (Part 2 of 2 – Memory Profiler)

- by ToStringTheory

One of the things that people might not know about me, is my obsession to make my code as efficient as possible. Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind… In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve. One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well. In this review, I am going to cover some of the features of the ANTS memory profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program. I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction – Part 2 In my last post, I reviewed the feature packed Red Gate ANTS Performance Profiler. Separate from the Red Gate Performance Profiler is the Red Gate ANTS Memory Profiler – a simple, easy to use utility for checking how your application is handling memory management… A tool that I wish I had had many times in the past. This post will be focusing on the ANTS Memory Profiler and its tool set. The memory profiler has a large assortment of features just like the Performance Profiler, with the new session looking nearly exactly alike: ANTS Memory Profiler Memory profiling is not something that I have to do very often… In the past, the few cases I’ve had to find a memory leak in an application I have usually just had to trace the code of the operations being performed to look for oddities… Sadly, I have come across more undisposed/non-using’ed IDisposable objects, usually from ADO.Net than I would like to ever see. Support is not fun, however using ANTS Memory Profiler makes this task easier. For this round of testing, I am going to use the same code from my previous example, using the WPF application. This time, I will choose the ‘Profile Memory’ option from the ANTS menu in Visual Studio, which launches the solution in its currently configured state/start-up project, and then launches the ANTS Memory Profiler to help. It prepopulates all of the fields with the current project information, and all I have to do is select the ‘Start Profiling’ option. When the window comes up, it is actually quite barren, just giving ideas on how to work the profiler. You start by getting to the point in your application that you want to profile, and then taking a ‘Memory Snapshot’. This performs a full garbage collection, and snapshots the managed heap. Using the same WPF app as before, I will go ahead and take a snapshot now. As you can see, ANTS is already giving me lots of information regarding the snapshot, however this is just a snapshot. The whole point of the profiler is to perform an action, usually one where a memory problem is being noticed, and then take another snapshot and perform a diff between them to see what has changed. I am going to go ahead and generate 5000 primes, and then take another snapshot: As you can see, ANTS is already giving me a lot of new information about this snapshot compared to the last. Information such as difference in memory usage, fragmentation, class usage, etc… If you take more snapshots, you can use the dropdown at the top to set your actual comparison snapshots. If you beneath the timeline, you will see a breadcrumb trail showing how best to approach profiling memory using ANTS. When you first do the comparison, you start on the Summary screen. You can either use the charts at the bottom, or switch to the class list screen to get to the next step. Here is the class list screen: As you can see, it lists information about all of the instances between the snapshots, as well as at the bottom giving you a way to filter by telling ANTS what your problem is. I am going to go ahead and select the Int16[] to look at the Instance Categorizer Using the instance categorizer, you can travel backwards to see where all of the instances are coming from. It may be hard to see in this image, but hopefully the lightbox (click on it) will help: I can see that all of these instances are rooted to the application through the UI TextBlock control. This image will probably be even harder to see, however using the ‘Instance Retention Graph’, you can trace an objects memory inheritance up the chain to see its roots as well. This is a simple example, as this is simply a known element. Usually you would be profiling an actual problem, and comparing those differences. I know in the past, I have spotted a problem where a new context was created per page load, and it was rooted into the application through an event. As the application began to grow, performance and reliability problems started to emerge. A tool like this would have been a great way to identify the problem quickly. Overview Overall, I think that the Red Gate ANTS Memory Profiler is a great utility for debugging those pesky leaks. 3 Biggest Pros: Easy to use interface with lots of options for configuring profiling session Intuitive and helpful interface for drilling down from summary, to instance, to root graphs ANTS provides an API for controlling the profiler. Not many options, but still helpful. 2 Biggest Cons: Inability to automatically snapshot the memory by interval Lack of complete integration with Visual Studio via an extension panel Ratings Ease of Use (9/10) – I really do believe that they have brought simplicity to the once difficult task of memory profiling. I especially liked how it stepped you further into the drilldown by directing you towards the best options. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do. Features (7/10) – A really great set of features all around in the application, however, I would like to see some ability for automatically triggering snapshots based on intervals or framework level items such as events. Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good. their people are friendly, helpful, and happy! UI / UX (9/10) – The interface is very easy to get around, and all of the options are easy to find. With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (9/10) – Overall, I am happy with the Memory Profiler and its features, as well as with the service I received when working with the Red Gate personnel. Thank you for reading up to here, or skipping ahead – I told you it would be shorter! Please, if you do try the product, drop me a message and let me know what you think! I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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List of freely available programming books

- by Karan Bhangui

I'm trying to amass a list of programming books with opensource licenses, like Creative Commons, GPL, etc. The books can be about a particular programming language or about computers in general. Hoping you guys could help: Languages BASH Advanced Bash-Scripting Guide (An in-depth exploration of the art of shell scripting) C The C book C++ Thinking in C++ C++ Annotations How to Think Like a Computer Scientist C# .NET Book Zero: What the C or C++ Programmer Needs to Know About C# and the .NET Framework Illustrated C# 2008 (Dead Link) Data Structures and Algorithms with Object-Oriented Design Patterns in C# Threading in C# Common Lisp Practical Common Lisp On Lisp Java Thinking in Java How to Think Like a Computer Scientist Java Thin-Client Programming JavaScript Eloquent JavaScript Haskell Real world Haskell Learn You a Haskell for Great Good! Objective-C The Objective-C Programming Language Perl Extreme Perl (license not specified - home page is saying "freely available") The Mason Book (Open Publication License) Practical mod_perl (CreativeCommons Attribution Share-Alike License) Higher-Order Perl Learning Perl the Hard Way PHP Practical PHP Programming Zend Framework: Survive the Deep End PowerShell Mastering PowerShell Prolog Building Expert Systems in Prolog Adventure in Prolog Prolog Programming A First Course Logic, Programming and Prolog (2ed) Introduction to Prolog for Mathematicians Learn Prolog Now! Natural Language Processing Techniques in Prolog Python Dive Into Python Dive Into Python 3 How to Think Like a Computer Scientist A Byte of Python Python for Fun Invent Your Own Computer Games With Python Ruby Why's (Poignant) Guide to Ruby Programming Ruby - The Pragmatic Programmer's Guide Mr. Neighborly's Humble Little Ruby Book SQL Practical PostgreSQL x86 assembly Paul Carter's tutorial Lua Programming In Lua (for v5 but still largely relevant) Algorithms and Data Structures Algorithms Data Structures and Algorithms with Object-Oriented Design Patterns in Java Planning Algorithms Frameworks/Projects The Django Book The Pylons Book Introduction to Design Patterns in C++ with Qt 4 (Open Publication License) Version control The SVN Book Mercurial: The Definitive Guide Pro Git UNIX / Linux The Art of Unix Programming Linux Device Drivers, Third Edition Others Structure and Interpretation of Computer Programs The Little Book of Semaphores Mathematical Logic - an Introduction An Introduction to the Theory of Computation Developers Developers Developers Developers Linkers and loaders Beej's Guide to Network Programming Maven: The Definitive Guide I will expand on this list as I get comments or when I think of more :D Related: Programming texts and reference material for my Kindle What are some good free programming books? Can anyone recommend a free software engineering book? Edit: Oh I didn't notice the community wiki feature. Feel free to edit your suggestions right in!

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Am I "wasting" my time learning C and other low level stuff ?

- by Andreas Grech

I have just recently started learning C and the reason I did that was because frankly, I consider myself to be of a "less-developer" than the people who know and work with C. Thus I planned to start learning ASM, C, C++ and bought the K&R book and started pushing myself to learn the C Programming Language and up till now I'm doing great...learning about arrays the low level way (ie the pointer + offset thing), pointers and all that and obviously asking questions on stackoverflow for guidance. My problem is that sometimes I get thinking if instead of learning this low level stuff, maybe I should maybe spend more time learning newer, more widely used technologies...basically, more web stuff. Now I am well versed with both C# and ASP.Net and currently that's what I do for a living, but still there exists Microsoft technologies that I haven't quite touched upon...such as ASP.Net MVC, The Entity Framework etc... And those are only Microsoft Technologies...obviously there are other stuff that I would like to touch upon...stuff like Ruby, which would lead me to Ruby on Rails, or Python for Django or even Java and J2EE, or maybe even PHP; ie, basically mainly Web Stuff. Mind you, I did touch upon some of the stuff I mentioned earlier on, such as PHP and Java but I am still not quite versed in them as I am in C# and ASP.Net...but still, I think that by learning other languages that are used in the web environment will broaden my horizons...both as a developer who loves learning, and also Career wise. My point is, am I really using up my time correctly by learning older, lower level stuff? Stuff that for my current line of work, will most probably never use, but still is interesting to know ? To be frankly honest, I am also learning C so that I could, maybe someday, get into Electronics and Micro-controller programming but that is a whole new world for me and, if I choose to go there, will take some time to get adjusted to. And even then, I don't know if I can get a career in working in that line of work. ...but I still wonder about this question over and over...Am I doing the right thing by learning C instead of something (Web-stuff) that will most probably be more useful for me career-wise? I'm sorry for such asking such a long and most probably a boring question, but I feel as if this is the only place where I can ask such a question and get an honest answer from experts in the field. Thank you for your time.

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How to merge jquery autocomplete and fcbkListSelection functionality?

- by Ben

Initial caveat: I am a newbie to jquery and javascript. I started using the autocomplete jquery plugin recently from bassistance.de. Yesterday, I found the fcbkListSelection plugin (http://www.emposha.com/javascript/fcbklistselection-like-facebook-friends-selector.html) and am using it to include a selector in my application. What I now want to do is to merge the 2 pieces of functionality since there are lots of items in my selector list. To be more specific, I want to put a "Filter by Name" text box above the facebook list selection object in my html. When the user types a few characters into the "Filter by Name" text box, I want the items in the Facebook list selector to only show the items that contain the typed characters -- kind of like what autocomplete does already, but rather than the results showing below the text input box, I want them to dynamically update the facebook list object. Is this possible and relatively straightforward? If so, can somebody please describe how to do it? If not, is there an easier way to approach this? Thanks! OK, to Spencer Ruport's comment, I guess I may have a more specific question already. Below is the current Javascript in my HTML file (angle brackets represent Django tags). #suggest1 and #fcbklist both do their separate pieces, but how do I get them to talk to each other? Do I need to further write javascript in my HTML file, or do I need to customize the guts of the plugins' .js? Does this help elaborate? $(document).ready(function() { var names = []; var count = 0; {% for a, b, c in friends_for_picker %} names[count] = "{{ b }}"; count = count+1; {% endfor %} function findValueCallback(event, data, formatted) { $("<li>").html( !data ? "No match!" : "Selected: " + formatted).appendTo("#result"); } function formatItem(row) { return row[0] + " (<strong>id: " + row[1] + "</strong>)"; } function formatResult(row) { return row[0].replace(/(<.+?>)/gi, ''); } $("#suggest1").autocomplete(names, { multiple: true, mustMatch: false, autoFill: true, matchContains: true, }); //id(ul id),width,height(element height),row(elements in row) $.fcbkListSelection("#fcbklist","575","50","4"); });

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A Python Wrapper for Shutterfly. Uploading an Image

- by iJames

I'm working on a Django app in which I want to order prints through Shutterfly's Open API: http://www.shutterfly.com/documentation/start.sfly So far I've been able to build the appropriate POSTs and GETs using the modules and suggested code snippets including httplib, httplib2, urllib, urllib2, mimetype, etc. But I'm stuck on the image uploading when placing an order (the ordering process is not the same process as uploading images to albums which I haven't tried.) From what I can tell, I'm supposed to basically create the multipart form data by concatenating the HTTP request body together with the binary data of the image. I take the strings: --myuniqueboundary1273149960.175.1 Content-Disposition: form-data; name="AuthenticationID" auniqueauthenticationid --myuniqueboundary1273149960.175.1 Content-Disposition: file; name="Image.Data"; filename="1_41_orig.jpg" Content-Type: image/jpeg and I put this data into it and end with the final boundary: ...\xb5|\xf88\x1dj\t@\xd9\'\x1f\xc6j\x88{\x8a\xc0\x18\x8eGaJG\x03\xe9J-\xd8\x96[\x91T\xc3\x0eTu\xf4\xaa\xa5Ty\x80\x01\x8c\x9f\xe9Z\xad\x8cg\xba# g\x18\xe2\xaa:\x829\x02\xb4["\x17Q\xe7\x801\xea?\xad7j\xfd\xa2\xdf\x81\xd2\x84D\xb6)\xa8\xcb\xc8O\\\x9a\xaf(\x1cqM\x98\x8d*\xb8\'h\xc8+\x8e:u\xaa\xf3*\x9b\x95\x05F8\xedN%\xcb\xe1B2\xa9~Tw\xedF\xc4\xfe\xe8\xfc\xa9\x983\xff\xd9... That ends up making it look like this (when I use print to debug): ... --myuniqueboundary1273149960.175.1 Content-Disposition: file; name="Image.Data"; filename="1_41_orig.jpg" Content-Type: image/jpeg ????q?ExifMM* ? ??(1?2?<??i?b?NIKON CORPORATIONNIKON D40HHQuickTime 7.62009:02:17 13:05:25Mac OS X 10.5.6%??????"?'??0220?????? ???? ? ?|_???,b???50??5 ... --myuniqueboundary1273149960.175.1-- My code for grabbing the binary data is pretty much this: filedata = open('myjpegfile.jpeg','rb').read() Which I then add to the rest of the body. I've see something like this code everywhere. I'm then using this to post the full request (with the headers too): response = urllib2.urlopen(request).read() This seems to me to be the standard way that form POSTS with files happens. Am I missing something here? At some point I might be able to make this into a library worth posting up on github, but this problem has stopped me cold in my tracks. Thanks for any insight!

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SQL efficiency argument, add a column or solvable by query?

- by theTurk

I am a recent college graduate and a new hire for software development. Things have been a little slow lately so I was given a db task. My db skills are limited to pet projects with Rails and Django. So, I was a little surprised with my latest task. I have been asked by my manager to subclass Person with a 'Parent' table and add a reference to their custodian in the Person table. This is to facilitate going from Parent to Form when the custodian, not the Parent, is the FormContact. Here is a simplified, mock structure of a sql-db I am working with. I would have drawn the relationship tables if I had access to Visio. We have a table 'Person' and we have a table 'Form'. There is a table, 'FormContact', that relates a Person to a Form, not all Persons are related to a Form. There is a relationship table for Person to Person relationships (Employer, Parent, etc.) I've asked, "Why this couldn't be handled by a query?" Response, Inefficient. (Really!?!) So, I ask, "Why not have a reference to the Form? That would be more efficient since you wouldn't be querying the FormContacts table with the reference from child/custodian." Response, this would essentially make the Parent is a FormContact. (Fair enough.) I went ahead an wrote a query to get from non-FormContact Parent to Form, and tested on the production server. The response time was instantaneous. *SOME_VALUE* is the Parent's fk ID. SELECT FormID FROM FormContact WHERE FormContact.ContactID IN (SELECT SourceContactID FROM ContactRelationship WHERE (ContactRelationship.RelatedContactID = *SOME_VALUE*) AND (ContactRelationship.Relationship = 'Parent')); If I am right, "This is an unnecessary change." What should I do, defend my position or should I concede to the managers request? If I am wrong. What is my error? Is there a better solution than the manager's?

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Python and displaying HTML

- by Tyler Seymour

I've gotten pretty comfortable with Python and now I'm looking to make a rudimentary web application. I was somewhat scared of Django and the other Python frameworks so I went caveman on it and decided to generate the HTML myself using another Python script. Maybe this is how you do it anyways - but I'm just figuring this stuff out. I'm really looking for a tip-off on, well, what to do next. My Python script PRINTS the HTML (is this even correct? I need it to be on a webpage!), but now what? Thanks for your continued support during my learning process. One day I will post answers! -Tyler Here's my code: from SearchPhone import SearchPhone phones = ["Iphone 3", "Iphone 4", "Iphone 5","Galaxy s3", "Galaxy s2", "LG Lucid", "LG Esteem", "HTC One S", "Droid 4", "Droid RAZR MAXX", "HTC EVO", "Galaxy Nexus", "LG Optimus 2", "LG Ignite", "Galaxy Note", "HTC Amaze", "HTC Rezound", "HTC Vivid", "HTC Rhyme", "Motorola Photon", "Motorola Milestone", "myTouch slide", "HTC Status", "Droid 3", "HTC Evo 3d", "HTC Wildfire", "LG Optimus 3d", "HTC ThunderBolt", "Incredible 2", "Kyocera Echo", "Galaxy S 4g", "HTC Inspire", "LG Optimus 2x", "Samsung Gem", "HTC Evo Shift", "Nexus S", "LG Axis", "Droid 2", "G2", "Droid x", "Droid Incredible" ] print """<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>table of phones</title> </head> <body> </body> </html> """ #table print '<table width="100%" border="1">' for x in phones: y = SearchPhone(x) print "\t<tr>" print "\t\t<td>" + str(y[0]) + "</td>" print "\t\t<td>" + str(y[1]) + "</td>" print "\t\t<td>" + str(y[2]) + "</td>" print "\t\t<td>" + str(y[3]) + "</td>" print "\t\t<td>" + str(y[4]) + "</td>" print "\t</tr>" print "</table>

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Simple jquery Fade Slideshow fails on certain browsers

- by cmay

So I have a simple slideshow on my website which just shows one image then shows another until it reaches the end or the user hits skip in which case it shows index.html. The site is served on apache2 with Django. The slideshow works perfectly on most machines, but certain machines it shows some images twice and other images not at all and the timing is off. I am using jquery 1.4.3. Below is the section of html where I push the image urls from the database to the javascript {% for image in latest_images %} {% thumbnail image.image_file "800x600" crop="center" as im %} <script>FadeImageList.push("{{im.url}}");</script> {% endthumbnail %} {% endfor %} Below is the full javascript file var FadeImageList = []; var fadeDuration = 2000; var fadeImgID = '#slideShow'; var homePageID = '#homePage'; var menuID = '#menu'; var skipFlag = 0; $(document).ready(function(){ $(homePageID).fadeOut(50); PlaySlideshow(FadeImageList); }); var PlaySlideshow = function(FadeImageList){ var newImgSrc = FadeImageList.shift(); $('#skip').click(function(){$('#loader').show();skipFlag = 1;}); if(((typeof(newImgSrc) !== "string") || (skipFlag === 1))){ EndSlideShow(); return; } else{ $(fadeImgID).fadeOut(fadeDuration,function(){ $(fadeImgID).attr('src', newImgSrc); $(fadeImgID).fadeIn(fadeDuration,function(){ PlaySlideshow(FadeImageList); }); }); } }; var EndSlideShow = function(fadeSettings){ $(fadeImgID).fadeOut(400,function(){ $(homePageID).fadeIn(400); $("#skip").fadeOut(400); $('#loader').hide(); }); }; The strange thing is I've had it work and fail on identically version numbered browsers on the same os but on different machines. It consistently either works or fails on a machine. I've had it fail in ie 7,8 firefox 3.6.3 and chrome. I've also had it succeed in ie6,7,8 firefox 3.6.3,3.4.2,3.1 and chrome.

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Can't get MySQL to install

- by James Marthenal

I'd like to think I know what I'm doing in a Unix shell but maybe not. I made a mistake in a configuration file for MySQL, so I decided to just uninstall it and then reinstall it, so I did: sudo apt-get --purge remove mysql-server mysql-server-5.0 mysql-client The files were deleted, so I then tried to install it, but it didn't ask me for a root password or anything else, so I uninstalled it using the above command again and then did sudo rm -rf /etc/mysql sudo rm /etc/init.d/mysql sudo rm -rf /var/lib/mysql* I then restarted the computer then installed it again: sudo apt-get install mysql-server mysql-client It asked for a root password, and everything looked like it would work, until I saw this: $ sudo apt-get install mysql-server mysql-client Reading package lists... Done Building dependency tree Reading state information... Done The following extra packages will be installed: mysql-server-5.0 Suggested packages: tinyca The following NEW packages will be installed: mysql-client mysql-server mysql-server-5.0 0 upgraded, 3 newly installed, 0 to remove and 1 not upgraded. Need to get 0B/27.4MB of archives. After this operation, 86.7MB of additional disk space will be used. Do you want to continue [Y/n]? y WARNING: The following packages cannot be authenticated! mysql-server-5.0 mysql-client mysql-server Authentication warning overridden. Preconfiguring packages ... Can't exec "/tmp/mysql-server-5.0.config.28101": Permission denied at /usr/share/perl/5.10/IPC/Open3.pm line 168. open2: exec of /tmp/mysql-server-5.0.config.28101 configure failed at /usr/share/perl5/Debconf/ConfModule.pm line 59 mysql-server-5.0 failed to preconfigure, with exit status 255 Selecting previously deselected package mysql-server-5.0. (Reading database ... 160284 files and directories currently installed.) Unpacking mysql-server-5.0 (from .../mysql-server-5.0_5.0.51a-24+lenny5_amd64.deb) ... Selecting previously deselected package mysql-client. Unpacking mysql-client (from .../mysql-client_5.0.51a-24+lenny5_all.deb) ... Selecting previously deselected package mysql-server. Unpacking mysql-server (from .../mysql-server_5.0.51a-24+lenny5_all.deb) ... Processing triggers for man-db ... Setting up mysql-server-5.0 (5.0.51a-24+lenny5) ... Stopping MySQL database server: mysqld. /var/lib/dpkg/info/mysql-server-5.0.postinst: line 144: /etc/mysql/conf.d/old_passwords.cnf: No such file or directory dpkg: error processing mysql-server-5.0 (--configure): subprocess post-installation script returned error exit status 1 Setting up mysql-client (5.0.51a-24+lenny5) ... dpkg: dependency problems prevent configuration of mysql-server: mysql-server depends on mysql-server-5.0; however: Package mysql-server-5.0 is not configured yet. dpkg: error processing mysql-server (--configure): dependency problems - leaving unconfigured Errors were encountered while processing: mysql-server-5.0 mysql-server E: Sub-process /usr/bin/dpkg returned an error code (1) Now I can't seem to figure out what to do. I just want to get a clean MySQL installation at this point. I'm running the latest stable release of Debian. All help is appreciated—thanks! Edit: I looked at this similar question, which suggests that I uninstall mysql-common, but when I try to do so I see: The following packages will be REMOVED: apache2 apache2-mpm-prefork apache2-utils apache2.2-common git-svn libapache2-mod-php5 libapache2-mod-python libapache2-svn libaprutil1 libdbd-mysql-perl libdbd-mysql-rubygem libmysql-ruby libmysql-ruby1.8 libmysql-rubygem libmysqlclient15-dev libmysqlclient15off librdf-perl librdf0 libserf-0-0 libsvn-perl libsvn1 mysql-client-5.0 mysql-common mytop ndn-apache22-php5 ndn-apache22-svn ndn-interpreters ndn-lighttpd ndn-netsaint-plugins ndn-perl-modules ndn-php5-cgi ndn-php5-xcache ndn-php53 ndn-php53-suhosin ndn-rubygems php5 php5-mcrypt php5-mysql proftpd proftpd-mod-mysql python-django python-mysqldb python-subversion python-svn subversion subversion-tools trac zendoptimizer 0 upgraded, 0 newly installed, 48 to remove and 1 not upgraded. Eeek! Any suggestions?

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Print driver installs failing

- by Kasius

All of the Windows 7 64-bit Enterprise machines in my organization are failing to install a good number of printer drivers that previously installed without issue. This only happens with printer drivers. And not with all printer drivers. Just some. Network drivers, video drivers, etc. have had no problems. Here is part of setupapi.dev.log for a Dymo LabelWriter printer driver that is failing to install: dvi: {Plug and Play Service: Device Install for USBPRINT\DYMOLABELWRITER_450_TURBO\6&538F51D&0&USB001} ump: Creating Install Process: DrvInst.exe 09:36:58.071 ndv: Infpath=C:\Windows\INF\oem0.inf ndv: DriverNodeName=dymo.inf:DYMO.NTamd64.6.0:LW_450_TURBO_VISTA:8.1.0.363:usbprint\dymolabelwriter_450_aa08 ndv: DriverStorepath=C:\Windows\System32\DriverStore\FileRepository\dymo.inf_amd64_neutral_3a631b118b7a5828\dymo.inf ndv: Building driver list from driver node strong name... dvi: Searching for hardware ID(s): dvi: usbprint\dymolabelwriter_450_aa08 dvi: dymolabelwriter_450_aa08 inf: Opened PNF: 'C:\Windows\System32\DriverStore\FileRepository\dymo.inf_amd64_neutral_3a631b118b7a5828\dymo.inf' ([strings]) dvi: Selected driver installs from section [LW_450_TURBO_VISTA] in 'c:\windows\system32\driverstore\filerepository\dymo.inf_amd64_neutral_3a631b118b7a5828\dymo.inf'. dvi: Class GUID of device changed to: {4d36e979-e325-11ce-bfc1-08002be10318}. dvi: Set selected driver complete. ndv: {Core Device Install} 09:36:58.133 inf: Opened INF: 'C:\Windows\INF\oem0.inf' ([strings]) inf: Saved PNF: 'C:\Windows\INF\oem0.PNF' (Language = 0409) dvi: {DIF_ALLOW_INSTALL} 09:36:58.164 dvi: Using exported function 'ClassInstall32' in module 'C:\Windows\system32\ntprint.dll'. dvi: Class installer == ntprint.dll,ClassInstall32 dvi: No CoInstallers found dvi: Class installer: Enter 09:36:58.164 dvi: Class installer: Exit dvi: Default installer: Enter 09:36:58.180 dvi: Default installer: Exit dvi: {DIF_ALLOW_INSTALL - exit(0xe000020e)} 09:36:58.180 ndv: Installing files... dvi: {DIF_INSTALLDEVICEFILES} 09:36:58.180 dvi: Class installer: Enter 09:36:58.180 inf: Opened INF: 'C:\Windows\System32\DriverStore\FileRepository\dymo.inf_amd64_neutral_3a631b118b7a5828\dymo.inf' ([strings]) inf: Opened INF: 'C:\Windows\System32\DriverStore\FileRepository\dymo.inf_amd64_neutral_3a631b118b7a5828\dymo.inf' ([strings]) !!! dvi: Class installer: failed(0x00000490)! !!! dvi: Error 1168: Element not found. dvi: {DIF_INSTALLDEVICEFILES - exit(0x00000490)} 09:37:22.063 ndv: Device install status=0x00000490 ndv: Performing device install final cleanup... ! ndv: Queueing up error report since device installation failed... ndv: {Core Device Install - exit(0x00000490)} 09:37:22.063 dvi: {DIF_DESTROYPRIVATEDATA} 09:37:22.063 dvi: Class installer: Enter 09:37:22.063 dvi: Class installer: Exit dvi: Default installer: Enter 09:37:22.063 dvi: Default installer: Exit dvi: {DIF_DESTROYPRIVATEDATA - exit(0xe000020e)} 09:37:22.063 ump: Server install process exited with code 0x00000490 09:37:22.063 ump: {Plug and Play Service: Device Install exit(00000490)} Notice these lines in particular: !!! dvi: Class installer: failed(0x00000490)! !!! dvi: Error 1168: Element not found. dvi: {DIF_INSTALLDEVICEFILES - exit(0x00000490)} 09:37:22.063 ndv: Device install status=0x00000490 From what I have read, the "Element not found" error should be accompanied by an event describing what element was not found. The error that appears in Device Manager is "The driver cannot be installed because it is either not digitally signed or not signed in the appropriate manner." It appears to be signed fine though. It has an accompanying .CAT file and worked previously. And when installing, the following messages are logged in setupapi.dev.log: sto: {DRIVERSTORE_IMPORT_NOTIFY_VALIDATE} 09:36:56.277 inf: Opened INF: 'C:\Windows\System32\DriverStore\Temp\{272e2305-961c-7942-9ede-966f01047043}\dymo.inf' ([strings]) sig: {_VERIFY_FILE_SIGNATURE} 09:36:56.292 sig: Key = dymo.inf sig: FilePath = C:\Windows\System32\DriverStore\Temp\{272e2305-961c-7942-9ede-966f01047043}\dymo.inf sig: Catalog = C:\Windows\System32\DriverStore\Temp\{272e2305-961c-7942-9ede-966f01047043}\DYMO.CAT sig: Success: File is signed in catalog. sig: {_VERIFY_FILE_SIGNATURE exit(0x00000000)} 09:36:56.355 sto: Validating driver package files against catalog 'DYMO.CAT'. sto: Driver package is valid. sto: {DRIVERSTORE_IMPORT_NOTIFY_VALIDATE exit(0x00000000)} 09:36:56.402 sto: Verified driver package signature: sto: Digital Signer Score = 0x0D000005 sto: Digital Signer Name = Microsoft Windows Hardware Compatibility Publisher Now here's where it gets strange. If I take it off the domain, it installs fine. But it doesn't seem to have anything to do with Group Policy. I moved the machine to an OU that blocks inheritance, ran a gpupdate, ran rsop.msc to verify, and tried again. And it still didn't work. Likewise, I removed a machine from the domain, manually set all of the domain Group Policy settings in gpedit.msc, and tried that way, and it worked fine. So it seems like the Group Policy settings are irrelevant. What other domain-related issue could be causing this though? Any ideas on what to try next would be greatly appreciated. I'm not sure where to go from here. Thanks!

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Incorrect gzipping of http requests, can't find who's doing it

- by Ned Batchelder

We're seeing some very strange mangling of HTTP responses, and we can't figure out what is doing it. We have an app server handling JSON requests. Occasionally, the response is returned gzipped, but with incorrect headers that prevent the browser from interpreting it correctly. The problem is intermittent, and changes behavior over time. Yesterday morning it seemed to fail 50% of the time, and in fact, seemed tied to one of our two load-balanced servers. Later in the afternoon, it was failing only 20 times out of 1000, and didn't correlate with an app server. The two app servers are running Apache 2.2 with mod_wsgi and a Django app stack. They have identical Apache configs and source trees, and even identical packages installed on Red Hat. There's a hardware load balancer in front, I don't know the make or model. Akamai is also part of the food chain, though we removed Akamai and still had the problem. Here's a good request and response: * Connected to example.com (97.7.79.129) port 80 (#0) > POST /claim/ HTTP/1.1 > User-Agent: curl/7.19.7 (x86_64-pc-linux-gnu) libcurl/7.19.7 OpenSSL/0.9.8k zlib/1.2.3.3 libidn/1.15 > Host: example.com > Accept: */* > Referer: http://example.com/apps/ > Accept-Encoding: gzip,deflate > Content-Length: 29 > Content-Type: application/x-www-form-urlencoded > } [data not shown] < HTTP/1.1 200 OK < Server: Apache/2 < Content-Language: en-us < Content-Encoding: identity < Content-Length: 47 < Content-Type: application/x-javascript < Connection: keep-alive < Vary: Accept-Encoding < { [data not shown] * Connection #0 to host example.com left intact * Closing connection #0 {"msg": "", "status": "OK", "printer_name": ""} And here's a bad one: * Connected to example.com (97.7.79.129) port 80 (#0) > POST /claim/ HTTP/1.1 > User-Agent: curl/7.19.7 (x86_64-pc-linux-gnu) libcurl/7.19.7 OpenSSL/0.9.8k zlib/1.2.3.3 libidn/1.15 > Host: example.com > Accept: */* > Referer: http://example.com/apps/ > Accept-Encoding: gzip,deflate > Content-Length: 29 > Content-Type: application/x-www-form-urlencoded > } [data not shown] < HTTP/1.1 200 OK < Server: Apache/2 < Content-Language: en-us < Content-Encoding: identity < Content-Type: application/x-javascript < Content-Encoding: gzip < Content-Length: 59 < Connection: keep-alive < Vary: Accept-Encoding < X-N: S < { [data not shown] * Connection #0 to host example.com left intact * Closing connection #0 ?V?-NW?RPR?QP*.I,)-???A??????????T??Z? ??/ There are two things to notice about the bad response: It has two Content-Encoding headers, and the browsers seem to use the first. So they see an identity encoding header, and gzipped content, so they can't interpret the response. The bad response has an extra "X-N: S" header. Perhaps if I could find out what intermediary adds "X-N: S" headers to responses, I could track down the culprit...

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Pluralsight Meet the Author Podcast on Structuring JavaScript Code

- by dwahlin

I had the opportunity to talk with Fritz Onion from Pluralsight about one of my recent courses titled Structuring JavaScript Code for one of their Meet the Author podcasts. We talked about why JavaScript patterns are important for building more re-useable and maintainable apps, pros and cons of different patterns, and how to go about picking a pattern as a project is started. The course provides a solid walk-through of converting what I call “Function Spaghetti Code” into more modular code that’s easier to maintain, more re-useable, and less susceptible to naming conflicts. Patterns covered in the course include the Prototype Pattern, Revealing Module Pattern, and Revealing Prototype Pattern along with several other tips and techniques that can be used. Meet the Author: Dan Wahlin on Structuring JavaScript Code The transcript from the podcast is shown below: [Fritz] Hello, this is Fritz Onion with another Pluralsight author interview. Today we’re talking with Dan Wahlin about his new course, Structuring JavaScript Code. Hi, Dan, it’s good to have you with us today. [Dan] Thanks for having me, Fritz. [Fritz] So, Dan, your new course, which came out in December of 2011 called Structuring JavaScript Code, goes into several patterns of usage in JavaScript as well as ways of organizing your code and what struck me about it was all the different techniques you described for encapsulating your code. I was wondering if you could give us just a little insight into what your motivation was for creating this course and sort of why you decided to write it and record it. [Dan] Sure. So, I got started with JavaScript back in the mid 90s. In fact, back in the days when browsers that most people haven’t heard of were out and we had JavaScript but it wasn’t great. I was on a project in the late 90s that was heavy, heavy JavaScript and we pretty much did what I call in the course function spaghetti code where you just have function after function, there’s no rhyme or reason to how those functions are structured, they just kind of flow and it’s a little bit hard to do maintenance on it, you really don’t get a lot of reuse as far as from an object perspective. And so coming from an object-oriented background in JAVA and C#, I wanted to put something together that highlighted kind of the new way if you will of writing JavaScript because most people start out just writing functions and there’s nothing with that, it works, but it’s definitely not a real reusable solution. So the course is really all about how to move from just kind of function after function after function to the world of more encapsulated code and more reusable and hopefully better maintenance in the process. [Fritz] So I am sure a lot of people have had similar experiences with their JavaScript code and will be looking forward to seeing what types of patterns you’ve put forth. Now, a couple I noticed in your course one is you start off with the prototype pattern. Do you want to describe sort of what problem that solves and how you go about using it within JavaScript? [Dan] Sure. So, the patterns that are covered such as the prototype pattern and the revealing module pattern just as two examples, you know, show these kind of three things that I harp on throughout the course of encapsulation, better maintenance, reuse, those types of things. The prototype pattern specifically though has a couple kind of pros over some of the other patterns and that is the ability to extend your code without touching source code and what I mean by that is let’s say you’re writing a library that you know either other teammates or other people just out there on the Internet in general are going to be using. With the prototype pattern, you can actually write your code in such a way that we’re leveraging the JavaScript property and by doing that now you can extend my code that I wrote without touching my source code script or you can even override my code and perform some new functionality. Again, without touching my code. And so you get kind of the benefit of the almost like inheritance or overriding in object oriented languages with this prototype pattern and it makes it kind of attractive that way definitely from a maintenance standpoint because, you know, you don’t want to modify a script I wrote because I might roll out version 2 and now you’d have to track where you change things and it gets a little tricky. So with this you just override those pieces or extend them and get that functionality and that’s kind of some of the benefits that that pattern offers out of the box. [Fritz] And then the revealing module pattern, how does that differ from the prototype pattern and what problem does that solve differently? [Dan] Yeah, so the prototype pattern and there’s another one that’s kind of really closely lined with revealing module pattern called the revealing prototype pattern and it also uses the prototype key word but it’s very similar to the one you just asked about the revealing module pattern. [Fritz] Okay. [Dan] This is a really popular one out there. In fact, we did a project for Microsoft that was very, very heavy JavaScript. It was an HMTL5 jQuery type app and we use this pattern for most of the structure if you will for the JavaScript code and what it does in a nutshell is allows you to get that encapsulation so you have really a single function wrapper that wraps all your other child functions but it gives you the ability to do public versus private members and this is kind of a sort of debate out there on the web. Some people feel that all JavaScript code should just be directly accessible and others kind of like to be able to hide their, truly their private stuff and a lot of people do that. You just put an underscore in front of your field or your variable name or your function name and that kind of is the defacto way to say hey, this is private. With the revealing module pattern you can do the equivalent of what objective oriented languages do and actually have private members that you literally can’t get to as an external consumer of the JavaScript code and then you can expose only those members that you want to be public. Now, you don’t get the benefit though of the prototype feature, which is I can’t easily extend the revealing module pattern type code if you don’t like something I’m doing, chances are you’re probably going to have to tweak my code to fix that because we’re not leveraging prototyping but in situations where you’re writing apps that are very specific to a given target app, you know, it’s not a library, it’s not going to be used in other apps all over the place, it’s a pattern I actually like a lot, it’s very simple to get going and then if you do like that public/private feature, it’s available to you. [Fritz] Yeah, that’s interesting. So it’s almost, you can either go private by convention just by using a standard naming convention or you can actually enforce it by using the prototype pattern. [Dan] Yeah, that’s exactly right. [Fritz] So one of the things that I know I run across in JavaScript and I’m curious to get your take on is we do have all these different techniques of encapsulation and each one is really quite different when you’re using closures versus simply, you know, referencing member variables and adding them to your objects that the syntax changes with each pattern and the usage changes. So what would you recommend for people starting out in a brand new JavaScript project? Should they all sort of decide beforehand on what patterns they’re going to stick to or do you change it based on what part of the library you’re working on? I know that’s one of the points of confusion in this space. [Dan] Yeah, it’s a great question. In fact, I just had a company ask me about that. So which one do I pick and, of course, there’s not one answer fits all. [Fritz] Right. [Dan] So it really depends what you just said is absolutely in my opinion correct, which is I think as a, especially if you’re on a team or even if you’re just an individual a team of one, you should go through and pick out which pattern for this particular project you think is best. Now if it were me, here’s kind of the way I think of it. If I were writing a let’s say base library that several web apps are going to use or even one, but I know that there’s going to be some pieces that I’m not really sure on right now as I’m writing I and I know people might want to hook in that and have some better extension points, then I would look at either the prototype pattern or the revealing prototype. Now, really just a real quick summation between the two the revealing prototype also gives you that public/private stuff like the revealing module pattern does whereas the prototype pattern does not but both of the prototype patterns do give you the benefit of that extension or that hook capability. So, if I were writing a library that I need people to override things or I’m not even sure what I need them to override, I want them to have that option, I’d probably pick a prototype, one of the prototype patterns. If I’m writing some code that is very unique to the app and it’s kind of a one off for this app which is what I think a lot of people are kind of in that mode as writing custom apps for customers, then my personal preference is the revealing module pattern you could always go with the module pattern as well which is very close but I think the revealing module patterns a little bit cleaner and we go through that in the course and explain kind of the syntax there and the differences. [Fritz] Great, that makes a lot of sense. [Fritz] I appreciate you taking the time, Dan, and I hope everyone takes a chance to look at your course and sort of make these decisions for themselves in their next JavaScript project. Dan’s course is, Structuring JavaScript Code and it’s available now in the Pluralsight Library. So, thank you very much, Dan. [Dan] Thanks for having me again.

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Fitting it together, database, reporting, applications in C#

- by alvonellos

Introduction Preamble I was hesitant to post this, since it's an application whose intricate details are defined elsewhere, and answers may not be helpful to others. Within the past few weeks (I was actually going to write a blog post about this after I finished) I've discovered that the barrier I'm encountering is one that's actually quite common for newer developers. This question is not so much about a specific thing as it is about piecing those things together. I've searched the internet far and wide, and found many tutorials on how to create applications that are kind of similar to what I'm looking for. I've also looked at hiring another, more experienced, developer to help me along, but all I've gotten are unqualified candidates that don't have the experience necessary and won't take care of the client or project like I will. I'd rather have the project never transpire than to release a solution that is half-baked. I've asked professors at my school, but they've not turned up answers to my question. I'm an experienced developer, and I've written many applications that are -- very abstractly -- close to what I'm doing, but my experiences from those applications aren't giving me enough leverage to solve this particular problem. I just hope that posting this article isn't a mistake for me to write. Project Description I have a project I'm working on for a client that is a rewrite of an application, originally written in Foxpro 2.6 by someone before me, that performs some analysis (which, sadly, I'm not allowed to disclose as per of my employment contract) on financial data. One day, after a long talk between the client and I -- where he intimately described his frustrations with all the bugs I've been hacking out of this code for 6 months now -- he told me to just rewrite it and gave me a month to write a good 1/8 of this 65k LOC Foxpro monstrosity. this 65k line of code foxpro monstrosity. It'll take me a good 3 - 6 months to rewrite this software (I know things the original programmer did not, like inheritance) going as I am right now, but I'm quickly discovering that I'm going to need to use databases. Prior to this contract I didn't even know about foxpro, and so I've had to learn foxpro on the fly, write procedures and make modifications to the database. I've actually come to like it, and this project would be rewritten in Foxpro if it were still a supported language, because over the past few months, I've come to like the features of Foxpro that make it so easy to develop data-driven applications. I once perfomed an experiment, comparing C# to Foxpro. What took me 45 minutes in C# took me two in Foxpro, and I knew C# prior to Foxpro. I was hoping to leverage the power of C#, but it intimidates me that in foxpro, you can have one line of code and be using a database. Prior to this, I have never written any serious database development from scratch. All the applications that I've written are in a different league. They are either completely data-naive or data-naive enough that I can get away with not using a database through serialization or by designing algorithms that work with the data in a manner that is stateless, so there is no need to worry about databases. I've come to realize, very quickly, that serialization and my efficacy with data structures has been my crutch all these years that's prevented me from adventuring into databases, and has consequently hindered my success in real-world programming. Sure, I've written some database stuff in Perl and Python, and I've done forms and worked with relational databases and tables, I'm a wizard in Access and Excel (seriously) and can do just about anything, but it just feels unnatural writing SQL code in another language... I don't mind writing SQL, and I don't It's that bridge between the database and the program code that drives me absolutely bonkers. I hope I'm not the only one to think this, but it bothers me that I have to create statements like the following string sSql = "SELECT * from tablename" When there's really no reason for that kind of unchecked language binding between two languages and two API's. Don't get my wrong, SQL is great, but I don't like the idea that, when executing commands on a SQL database, that one must intermix database and application software, and there's no database independence, which means that different versions of different databases can break code. This isn't very nice. The nicest thing about Foxpro is the cohesiveness between programming language and database. It's so easy, and Foxpro makes it easy, because the tool just fits the task. I can see why so many developers have created a career with this language, because it lowered the barrier of entry to data-driven applications that so many businesses need. It was wonderful. For my purposes today, with the demands and need for community support, extensibility, and language features, Foxpro isn't a solution that I feel would be the right tool for the job. I'm also worried about working too heavy with the database, because I've seen data-driven .NET applications have issues with database caches, running out of memory, and objects in the database not being collected. (Memory leaks) And OH the queries. Which one, how, and why? There are a plethora of different ways that a database can be setup, I think I counted 5 or 6 different kinds of database applications alone that I can chose from. That is a great mountain for me to climb when I don't even know where to begin when it comes to writing data-driven applications. The problem isn't that I don't know SQL or that I don't know C#. I know both and have worked with both extensively. It's making them work together that's the problem, and it's something I've never done in C# before. Reports The client likes paper. The data needs to be printed out in a format that is extensible, layered, and easy to use. I have never done reporting before, and so this is a bit of a problem. From the data source comes crystal reports, and so there's a dependency on the database, from what I understand. Code reuse A large part of the design decision that I've gone through so far is to break the task of writing a piece of this software into routines and modular DLL's and so forth such that much of the code can be reused. For example, when I setup this database, I want to be able to reuse the same database code over and over again. I also want to make sure that when the day comes that another developer is here, that he/she will be able to pick up just where I left off. The quicker I develop these applications, the better off I am. Tasks & Goals In my project, I need to write routines that apply algorithms and look for predefined patterns in financial data. Additionally, I need to simulate trading based on predefined algorithms and data. Then I need to prepare reports on that data. Additionally, I need to have a way to change the code base for this application quickly and effectively, without hacking together some band-aid solution for a problem that really needs a trauma ward. Special Considerations The solution must be fast, run quickly on existing hardware, and not be too much of a pain to maintain and write. I understand that anything I write I'm married to -- I'm responsible for the things that I write because my reputation and livelihood is dependent on it. Do I really need a database? What about performance? Performance was such a big issue that I hand wrote a data structure that is capable of performing 2 billion operations, using a total of 4 gigs of memory in under 1/4 of a second using the standard core two duo processor. I could not find a similar, pre-written data structure in C# to perform this task. What setup do I use in terms of database? What about reporting? I'd prefer to have PDF's generated, but I'd like to be able to visually sketch those reports and then just have a ReportFactory of some sort, that when I pass some variables in, it just does that data. About Me I'm a lone developer for a small business in this area. This is the first time I've done this and I've never had the breadth and depth of my knowledge tested. I'm incredibly frustrated with this project because I feel incredibly overwhelmed with the task at hand. I'm looking for that entry level point where I can draw a line and say "this is what I need to do" Conclusion I may have not been clear enough on my post. I'm still new to this whole thing, and I've been doing my best to contribute back to the community that I've leached so much knowledge from. I'd be glad to edit my post and add more information if possible. I'm looking for a big-picture solution or design process that helps me get off the ground in this world of data-driven applications, because I have a feeling that it's going to be concentric to my entire career as a programmer for some time. Specifically, if you didn't get it from the rest of the post (I may not have been clear enough) I really need some guidance as to where to go in terms of the design decisions for this project. Some things that'll be useful will be a pro/con list for the different kinds of database projects available in VS2010. I've tried, but generating that list has been as hard as solving the problem itself... If you could walk a developer writing a data-driven application for the first time in C#, how would you do that? Where would you point them to?

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Demystifying Silverlight Dependency Properties

- by dwahlin

I have the opportunity to teach a lot of people about Silverlight (amongst other technologies) and one of the topics that definitely confuses people initially is the concept of dependency properties. I confess that when I first heard about them my initial thought was “Why do we need a specialized type of property?” While you can certainly use standard CLR properties in Silverlight applications, Silverlight relies heavily on dependency properties for just about everything it does behind the scenes. In fact, dependency properties are an essential part of the data binding, template, style and animation functionality available in Silverlight. They simply back standard CLR properties. In this post I wanted to put together a (hopefully) simple explanation of dependency properties and why you should care about them if you’re currently working with Silverlight or looking to move to it. What are Dependency Properties? XAML provides a great way to define layout controls, user input controls, shapes, colors and data binding expressions in a declarative manner. There’s a lot that goes on behind the scenes in order to make XAML work and an important part of that magic is the use of dependency properties. If you want to bind data to a property, style it, animate it or transform it in XAML then the property involved has to be a dependency property to work properly. If you’ve ever positioned a control in a Canvas using Canvas.Left or placed a control in a specific Grid row using Grid.Row then you’ve used an attached property which is a specialized type of dependency property. Dependency properties play a key role in XAML and the overall Silverlight framework. Any property that you bind, style, template, animate or transform must be a dependency property in Silverlight applications. You can programmatically bind values to controls and work with standard CLR properties, but if you want to use the built-in binding expressions available in XAML (one of my favorite features) or the Binding class available through code then dependency properties are a necessity. Dependency properties aren’t needed in every situation, but if you want to customize your application very much you’ll eventually end up needing them. For example, if you create a custom user control and want to expose a property that consumers can use to change the background color, you have to define it as a dependency property if you want bindings, styles and other features to be available for use. Now that the overall purpose of dependency properties has been discussed let’s take a look at how you can create them. Creating Dependency Properties When .NET first came out you had to write backing fields for each property that you defined as shown next: Brush _ScheduleBackground; public Brush ScheduleBackground { get { return _ScheduleBackground; } set { _ScheduleBackground = value; } } Although .NET 2.0 added auto-implemented properties (for example: public Brush ScheduleBackground { get; set; }) where the compiler would automatically generate the backing field used by get and set blocks, the concept is still the same as shown in the above code; a property acts as a wrapper around a field. Silverlight dependency properties replace the _ScheduleBackground field shown in the previous code and act as the backing store for a standard CLR property. The following code shows an example of defining a dependency property named ScheduleBackgroundProperty: public static readonly DependencyProperty ScheduleBackgroundProperty = DependencyProperty.Register("ScheduleBackground", typeof(Brush), typeof(Scheduler), null); Looking through the code the first thing that may stand out is that the definition for ScheduleBackgroundProperty is marked as static and readonly and that the property appears to be of type DependencyProperty. This is a standard pattern that you’ll use when working with dependency properties. You’ll also notice that the property explicitly adds the word “Property” to the name which is another standard you’ll see followed. In addition to defining the property, the code also makes a call to the static DependencyProperty.Register method and passes the name of the property to register (ScheduleBackground in this case) as a string. The type of the property, the type of the class that owns the property and a null value (more on the null value later) are also passed. In this example a class named Scheduler acts as the owner. The code handles registering the property as a dependency property with the call to Register(), but there’s a little more work that has to be done to allow a value to be assigned to and retrieved from the dependency property. The following code shows the complete code that you’ll typically use when creating a dependency property. You can find code snippets that greatly simplify the process of creating dependency properties out on the web. The MVVM Light download available from http://mvvmlight.codeplex.com comes with built-in dependency properties snippets as well. public static readonly DependencyProperty ScheduleBackgroundProperty = DependencyProperty.Register("ScheduleBackground", typeof(Brush), typeof(Scheduler), null); public Brush ScheduleBackground { get { return (Brush)GetValue(ScheduleBackgroundProperty); } set { SetValue(ScheduleBackgroundProperty, value); } } The standard CLR property code shown above should look familiar since it simply wraps the dependency property. However, you’ll notice that the get and set blocks call GetValue and SetValue methods respectively to perform the appropriate operation on the dependency property. GetValue and SetValue are members of the DependencyObject class which is another key component of the Silverlight framework. Silverlight controls and classes (TextBox, UserControl, CompositeTransform, DataGrid, etc.) ultimately derive from DependencyObject in their inheritance hierarchy so that they can support dependency properties. Dependency properties defined in Silverlight controls and other classes tend to follow the pattern of registering the property by calling Register() and then wrapping the dependency property in a standard CLR property (as shown above). They have a standard property that wraps a registered dependency property and allows a value to be assigned and retrieved. If you need to expose a new property on a custom control that supports data binding expressions in XAML then you’ll follow this same pattern. Dependency properties are extremely useful once you understand why they’re needed and how they’re defined. Detecting Changes and Setting Defaults When working with dependency properties there will be times when you want to assign a default value or detect when a property changes so that you can keep the user interface in-sync with the property value. Silverlight’s DependencyProperty.Register() method provides a fourth parameter that accepts a PropertyMetadata object instance. PropertyMetadata can be used to hook a callback method to a dependency property. The callback method is called when the property value changes. PropertyMetadata can also be used to assign a default value to the dependency property. By assigning a value of null for the final parameter passed to Register() you’re telling the property that you don’t care about any changes and don’t have a default value to apply. Here are the different constructor overloads available on the PropertyMetadata class: PropertyMetadata Constructor Overload Description PropertyMetadata(Object) Used to assign a default value to a dependency property. PropertyMetadata(PropertyChangedCallback) Used to assign a property changed callback method. PropertyMetadata(Object, PropertyChangedCalback) Used to assign a default property value and a property changed callback. There are many situations where you need to know when a dependency property changes or where you want to apply a default. Performing either task is easily accomplished by creating a new instance of the PropertyMetadata class and passing the appropriate values to its constructor. The following code shows an enhanced version of the initial dependency property code shown earlier that demonstrates these concepts: public Brush ScheduleBackground { get { return (Brush)GetValue(ScheduleBackgroundProperty); } set { SetValue(ScheduleBackgroundProperty, value); } } public static readonly DependencyProperty ScheduleBackgroundProperty = DependencyProperty.Register("ScheduleBackground", typeof(Brush), typeof(Scheduler), new PropertyMetadata(new SolidColorBrush(Colors.LightGray), ScheduleBackgroundChanged)); private static void ScheduleBackgroundChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { var scheduler = d as Scheduler; scheduler.Background = e.NewValue as Brush; } The code wires ScheduleBackgroundProperty to a property change callback method named ScheduleBackgroundChanged. What’s interesting is that this callback method is static (as is the dependency property) so it gets passed the instance of the object that owns the property that has changed (otherwise we wouldn’t be able to get to the object instance). In this example the dependency object is cast to a Scheduler object and its Background property is assigned to the new value of the dependency property. The code also handles assigning a default value of LightGray to the dependency property by creating a new instance of a SolidColorBrush. To Sum Up In this post you’ve seen the role of dependency properties and how they can be defined in code. They play a big role in XAML and the overall Silverlight framework. You can think of dependency properties as being replacements for fields that you’d normally use with standard CLR properties. In addition to a discussion on how dependency properties are created, you also saw how to use the PropertyMetadata class to define default dependency property values and hook a dependency property to a callback method. The most important thing to understand with dependency properties (especially if you’re new to Silverlight) is that they’re needed if you want a property to support data binding, animations, transformations and styles properly. Any time you create a property on a custom control or user control that has these types of requirements you’ll want to pick a dependency property over of a standard CLR property with a backing field. There’s more that can be covered with dependency properties including a related property called an attached property….more to come.

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