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• SSIS - user variable used in derived column transform is not available - in some cases

  - by soo

  Unfortunately I don't have a repro for my issue, but I thought I would try to describe it in case it sounds familiar to someone... I am using SSIS 2005, SP2. My package has a package-scope user variable - let's call it user_var first step in the control flow is an Execute SQL task which runs a stored procedure. All that SP does is insert a record in a SQL table (with an identity column) and then go back and get the max ID value. The Execute SQL task saves this output into user_var the control flow then has a Data Flow Task - it goes and gets some source data, has a derived column which sets a column called run_id to user_var - and saves the data to a SQL destination In most cases (this template is used for many packages, running every day) this all works great. All of the destination records created get set with a correct run_id. However, in some cases, there is a set of the destination data that does not get run_id equal to user_var, but instead gets a value of 0 (0 is the default value for user_var). I have 2 instances where this has happened, but I can't make it happen. In both cases, it was just less that 10,000 records that have run_id = 0. Since SSIS writes data out in 10,000 record blocks, this really makes me think that, for the first set of data written out, user_var was not yet set. Then, after that first block, for the rest of the data, run_id is set to a correct value. But control passed on to my data flow from the Execute SQL task - it would have seemed reasonable to me that it wouldn't go on until the SP has completed and user_var is set. Maybe it just runs the SP, but doesn't wait for it to complete? In both cases where this has happened there seemed to be a few packages hitting the table to get a new user_var at about the same time. And in both cases lots of data was written (40 million rows, 60 million rows) - my thinking is that that means the writes were happening for a while. Sorry to be both long-winded AND vague. A winning combination! Does this sound familiar to anyone? Thanks.

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• Efficient method of finding database rows that have *one or more* qualities from a list of seven qualities

  - by hithere

  Hello! For this question, I'm looking to see if anyone has a better idea of how to implement what I'm currently planning on implementing (below): I'm keeping track of a set of images, using a database. Each image is represented by one row. I want to be able to search for images, using a number of different search parameters. One of these parameters involves a search-by-color option. (The rest of the search stuff is currently working fine.) Images in this database can contain up to seven colors: -Red -Orange -Yellow -Green -Blue -Indigo -Violet Here are some example user queries: "I want an image that contains red." "I want an image that contains red and blue." "I want an image that contains yellow and violet." "I want an image that contains red, orange, yellow, green, blue, indigo and violet." And so on. Users make this selection through the use of checkboxes in an html form. They can check zero checkboxes, all seven, and anything in between. I'm curious to hear what people think would be the most efficient way to perform this database search. I have two possible options right now, but I feel like there must be something better that I'm not thinking of. (Option 1) -For each row, simply have seven additional fields in the database, one for each color. Each field holds a 1 or 0 (true/false) value, and I SELECT based on whatever the user has checked off. (I didn't like this solution so much, because it seemed kind of wasteful to add seven additional fields...especially since most pictures in this table will only have 3-4 colors max, though some could have up to 7. So that means I'm storing a lot of zeros.) Also, if I added more searchable colors later on (which I don't think I will, but it's always possible), I'd have to add more fields. (Option 2) -For each image row, I could have a "colors" text field that stores space-separated color names (or numbers for the sake of compactness). Then I could do a fulltext match against search through the fields, selecting rows that contain "red yellow green" (or "1 3 4"). But I kind of didn't want to do fulltext searching because I already allow a keyword search, and I didn't really want to do two fulltext searches per image search. Plus, if the database gets big, fulltext stuff might slow down. Any better options that I didn't think of? Thanks! Side Note: I'm using PHP to work with a MySQL database.

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• Java Sorting "queue" list based on DateTime and Z Position (part of school project)

  - by Kuchinawa

  For a school project i have a list of 50k containers that arrive on a boat. These containers need to be sorted in a list in such a way that the earliest departure DateTimes are at the top and the containers above those above them. This list then gets used for a crane that picks them up in order. I started out with 2 Collection.sort() methods: 1st one to get them in the right XYZ order Collections.sort(containers, new Comparator<ContainerData>() { @Override public int compare(ContainerData contData1, ContainerData contData2) { return positionSort(contData1.getLocation(),contData2.getLocation()); } }); Then another one to reorder the dates while keeping the position in mind: Collections.sort(containers, new Comparator<ContainerData>() { @Override public int compare(ContainerData contData1, ContainerData contData2) { int c = contData1.getLeaveDateTimeFrom().compareTo(contData2.getLeaveDateTimeFrom()); int p = positionSort2(contData1.getLocation(), contData2.getLocation()); if(p != 0) c = p; return c; } }); But i never got this method to work.. What i got working now is rather quick and dirty and takes a long time to process (50seconds for all 50k): First a sort on DateTime: Collections.sort(containers, new Comparator<ContainerData>() { @Override public int compare(ContainerData contData1, ContainerData contData2) { return contData1.getLeaveDateTimeFrom().compareTo(contData2.getLeaveDateTimeFrom()); } }); Then a correction function that bumps top containers up: containers = stackCorrection(containers); private static List<ContainerData> stackCorrection(List<ContainerData> sortedContainerList) { for(int i = 0; i < sortedContainerList.size(); i++) { ContainerData current = sortedContainerList.get(i); // 5 = Max Stack (0 index) if(current.getLocation().getZ() < 5) { //Loop through possible containers above current for(int j = 5; j > current.getLocation().getZ(); --j) { //Search for container above for(int k = i + 1; k < sortedContainerList.size(); ++k) if(sortedContainerList.get(k).getLocation().getX() == current.getLocation().getX()) { if(sortedContainerList.get(k).getLocation().getY() == current.getLocation().getY()) { if(sortedContainerList.get(k).getLocation().getZ() == j) { //Found -> move container above current sortedContainerList.add(i, sortedContainerList.remove(k)); k = sortedContainerList.size(); i++; } } } } } } return sortedContainerList; } I would like to implement this in a better/faster way. So any hints are appreciated. :)

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• How can I scale movement physics functions to frames per second (in a game engine)?

  - by Richard

  I am working on a game in Javascript (HTML5 Canvas). I implemented a simple algorithm that allows an object to follow another object with basic physics mixed in (a force vector to drive the object in the right direction, and the velocity stacks momentum, but is slowed by a constant drag force). At the moment, I set it up as a rectangle following the mouse (x, y) coordinates. Here's the code: // rectangle x, y position var x = 400; // starting x position var y = 250; // starting y position var FPS = 60; // frames per second of the screen // physics variables: var velX = 0; // initial velocity at 0 (not moving) var velY = 0; // not moving var drag = 0.92; // drag force reduces velocity by 8% per frame var force = 0.35; // overall force applied to move the rectangle var angle = 0; // angle in which to move // called every frame (at 60 frames per second): function update(){ // calculate distance between mouse and rectangle var dx = mouseX - x; var dy = mouseY - y; // calculate angle between mouse and rectangle var angle = Math.atan(dy/dx); if(dx < 0) angle += Math.PI; else if(dy < 0) angle += 2*Math.PI; // calculate the force (on or off, depending on user input) var curForce; if(keys[32]) // SPACE bar curForce = force; // if pressed, use 0.35 as force else curForce = 0; // otherwise, force is 0 // increment velocty by the force, and scaled by drag for x and y velX += curForce * Math.cos(angle); velX *= drag; velY += curForce * Math.sin(angle); velY *= drag; // update x and y by their velocities x += velX; y += velY; And that works fine at 60 frames per second. Now, the tricky part: my question is, if I change this to a different framerate (say, 30 FPS), how can I modify the force and drag values to keep the movement constant? That is, right now my rectangle (whose position is dictated by the x and y variables) moves at a maximum speed of about 4 pixels per second, and accelerates to its max speed in about 1 second. BUT, if I change the framerate, it moves slower (e.g. 30 FPS accelerates to only 2 pixels per frame). So, how can I create an equation that takes FPS (frames per second) as input, and spits out correct "drag" and "force" values that will behave the same way in real time? I know it's a heavy question, but perhaps somebody with game design experience, or knowledge of programming physics can help. Thank you for your efforts. jsFiddle: http://jsfiddle.net/BadDB

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• MEF CompositionInitializer for WPF

  - by Reed

  The Managed Extensibility Framework is an amazingly useful addition to the .NET Framework.  I was very excited to see System.ComponentModel.Composition added to the core framework.  Personally, I feel that MEF is one tool I’ve always been missing in my .NET development. Unfortunately, one perfect scenario for MEF tends to fall short of it’s full potential is in Windows Presentation Foundation development.  In particular, there are many times when the XAML parser constructs objects in WPF development, which makes composition of those parts difficult.  The current release of MEF (Preview Release 9) addresses this for Silverlight developers via System.ComponentModel.Composition.CompositionInitializer.  However, there is no equivalent class for WPF developers. The CompositionInitializer class provides the means for an object to compose itself.  This is very useful with WPF and Silverlight development, since it allows a View, such as a UserControl, to be generated via the standard XAML parser, and still automatically pull in the appropriate ViewModel in an extensible manner.  Glenn Block has demonstrated the usage for Silverlight in detail, but the same issues apply in WPF. As an example, let’s take a look at a very simple case.  Take the following XAML for a Window: <Window x:Class="WpfApplication1.MainView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow" Height="220" Width="300"> <Grid> <TextBlock Text="{Binding TheText}" /> </Grid> </Window> This does nothing but create a Window, add a simple TextBlock control, and use it to display the value of our “TheText” property in our DataContext class.  Since this is our main window, WPF will automatically construct and display this Window, so we need to handle constructing the DataContext and setting it ourselves. We could do this in code or in XAML, but in order to do it directly, we would need to hard code the ViewModel type directly into our XAML code, or we would need to construct the ViewModel class and set it in the code behind.  Both have disadvantages, and the disadvantages grow if we’re using MEF to compose our ViewModel. Ideally, we’d like to be able to have MEF construct our ViewModel for us.  This way, it can provide any construction requirements for our ViewModel via [ImportingConstructor], and it can handle fully composing the imported properties on our ViewModel.  CompositionInitializer allows this to occur. We use CompositionInitializer within our View’s constructor, and use it for self-composition of our View.  Using CompositionInitializer, we can modify our code behind to: public partial class MainView : Window { public MainView() { InitializeComponent(); CompositionInitializer.SatisfyImports(this); } [Import("MainViewModel")] public object ViewModel { get { return this.DataContext; } set { this.DataContext = value; } } } We then can add an Export on our ViewModel class like so: [Export("MainViewModel")] public class MainViewModel { public string TheText { get { return "Hello World!"; } } } MEF will automatically compose our application, decoupling our ViewModel injection to the DataContext of our View until runtime.  When we run this, we’ll see: There are many other approaches for using MEF to wire up the extensible parts within your application, of course.  However, any time an object is going to be constructed by code outside of your control, CompositionInitializer allows us to continue to use MEF to satisfy the import requirements of that object. In order to use this from WPF, I’ve ported the code from MEF Preview 9 and Glenn Block’s (now obsolete) PartInitializer port to Windows Presentation Foundation.  There are some subtle changes from the Silverlight port, mainly to handle running in a desktop application context.  The default behavior of my port is to construct an AggregateCatalog containing a DirectoryCatalog set to the location of the entry assembly of the application.  In addition, if an “Extensions” folder exists under the entry assembly’s directory, a second DirectoryCatalog for that folder will be included.  This behavior can be overridden by specifying a CompositionContainer or one or more ComposablePartCatalogs to the System.ComponentModel.Composition.Hosting.CompositionHost static class prior to the first use of CompositionInitializer. Please download CompositionInitializer and CompositionHost for VS 2010 RC, and contact me with any feedback. Composition.Initialization.Desktop.zip Edit on 3/29: Glenn Block has since updated his version of CompositionInitializer (and ExportFactory<T>!), and made it available here: http://cid-f8b2fd72406fb218.skydrive.live.com/self.aspx/blog/Composition.Initialization.Desktop.zip This is a .NET 3.5 solution, and should soon be pushed to CodePlex, and made available on the main MEF site.

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• LINQ to SQL and missing Many to Many EntityRefs

  - by Rick Strahl

  Ran into an odd behavior today with a many to many mapping of one of my tables in LINQ to SQL. Many to many mappings aren’t transparent in LINQ to SQL and it maps the link table the same way the SQL schema has it when creating one. In other words LINQ to SQL isn’t smart about many to many mappings and just treats it like the 3 underlying tables that make up the many to many relationship. Iain Galloway has a nice blog entry about Many to Many relationships in LINQ to SQL. I can live with that – it’s not really difficult to deal with this arrangement once mapped, especially when reading data back. Writing is a little more difficult as you do have to insert into two entities for new records, but nothing that can’t be handled in a small business object method with a few lines of code. When I created a database I’ve been using to experiment around with various different OR/Ms recently I found that for some reason LINQ to SQL was completely failing to map even to the linking table. As it turns out there’s a good reason why it fails, can you spot it below? (read on :-}) Here is the original database layout: There’s an items table, a category table and a link table that holds only the foreign keys to the Items and Category tables for a typical M->M relationship. When these three tables are imported into the model the *look* correct – I do get the relationships added (after modifying the entity names to strip the prefix): The relationship looks perfectly fine, both in the designer as well as in the XML document: <Table Name="dbo.wws_Item_Categories" Member="ItemCategories"> <Type Name="ItemCategory"> <Column Name="ItemId" Type="System.Guid" DbType="uniqueidentifier NOT NULL" CanBeNull="false" /> <Column Name="CategoryId" Type="System.Guid" DbType="uniqueidentifier NOT NULL" CanBeNull="false" /> <Association Name="ItemCategory_Category" Member="Categories" ThisKey="CategoryId" OtherKey="Id" Type="Category" /> <Association Name="Item_ItemCategory" Member="Item" ThisKey="ItemId" OtherKey="Id" Type="Item" IsForeignKey="true" /> </Type> </Table> <Table Name="dbo.wws_Categories" Member="Categories"> <Type Name="Category"> <Column Name="Id" Type="System.Guid" DbType="UniqueIdentifier NOT NULL" IsPrimaryKey="true" IsDbGenerated="true" CanBeNull="false" /> <Column Name="ParentId" Type="System.Guid" DbType="UniqueIdentifier" CanBeNull="true" /> <Column Name="CategoryName" Type="System.String" DbType="NVarChar(150)" CanBeNull="true" /> <Column Name="CategoryDescription" Type="System.String" DbType="NVarChar(MAX)" CanBeNull="true" /> <Column Name="tstamp" AccessModifier="Internal" Type="System.Data.Linq.Binary" DbType="rowversion" CanBeNull="true" IsVersion="true" /> <Association Name="ItemCategory_Category" Member="ItemCategory" ThisKey="Id" OtherKey="CategoryId" Type="ItemCategory" IsForeignKey="true" /> </Type> </Table> However when looking at the code generated these navigation properties (also on Item) are completely missing: [global::System.Data.Linq.Mapping.TableAttribute(Name="dbo.wws_Item_Categories")] [global::System.Runtime.Serialization.DataContractAttribute()] public partial class ItemCategory : Westwind.BusinessFramework.EntityBase { private System.Guid _ItemId; private System.Guid _CategoryId; public ItemCategory() { } [global::System.Data.Linq.Mapping.ColumnAttribute(Storage="_ItemId", DbType="uniqueidentifier NOT NULL")] [global::System.Runtime.Serialization.DataMemberAttribute(Order=1)] public System.Guid ItemId { get { return this._ItemId; } set { if ((this._ItemId != value)) { this._ItemId = value; } } } [global::System.Data.Linq.Mapping.ColumnAttribute(Storage="_CategoryId", DbType="uniqueidentifier NOT NULL")] [global::System.Runtime.Serialization.DataMemberAttribute(Order=2)] public System.Guid CategoryId { get { return this._CategoryId; } set { if ((this._CategoryId != value)) { this._CategoryId = value; } } } } Notice that the Item and Category association properties which should be EntityRef properties are completely missing. They’re there in the model, but the generated code – not so much. So what’s the problem here? The problem – it appears – is that LINQ to SQL requires primary keys on all entities it tracks. In order to support tracking – even of the link table entity – the link table requires a primary key. Real obvious ain’t it, especially since the designer happily lets you import the table and even shows the relationship and implicitly the related properties. Adding an Id field as a Pk to the database and then importing results in this model layout: which properly generates the Item and Category properties into the link entity. It’s ironic that LINQ to SQL *requires* the PK in the middle – the Entity Framework requires that a link table have *only* the two foreign key fields in a table in order to recognize a many to many relation. EF actually handles the M->M relation directly without the intermediate link entity unlike LINQ to SQL. [updated from comments – 12/24/2009] Another approach is to set up both ItemId and CategoryId in the database which shows up in LINQ to SQL like this: This also work in creating the Category and Item fields in the ItemCategory entity. Ultimately this is probably the best approach as it also guarantees uniqueness of the keys and so helps in database integrity. It took me a while to figure out WTF was going on here – lulled by the designer to think that the properties should be when they were not. It’s actually a well documented feature of L2S that each entity in the model requires a Pk but of course that’s easy to miss when the model viewer shows it to you and even the underlying XML model shows the Associations properly. This is one of the issue with L2S of course – you have to play by its rules and once you hit one of those rules there’s no way around them – you’re stuck with what it requires which in this case meant changing the database.© Rick Strahl, West Wind Technologies, 2005-2010Posted in ADO.NET  LINQ  

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• C# 5 Async, Part 1: Simplifying Asynchrony – That for which we await

  - by Reed

  Today’s announcement at PDC of the future directions C# is taking excite me greatly.  The new Visual Studio Async CTP is amazing.  Asynchronous code – code which frustrates and demoralizes even the most advanced of developers, is taking a huge leap forward in terms of usability.  This is handled by building on the Task functionality in .NET 4, as well as the addition of two new keywords being added to the C# language: async and await. This core of the new asynchronous functionality is built upon three key features.  First is the Task functionality in .NET 4, and based on Task and Task<TResult>.  While Task was intended to be the primary means of asynchronous programming with .NET 4, the .NET Framework was still based mainly on the Asynchronous Pattern and the Event-based Asynchronous Pattern. The .NET Framework added functionality and guidance for wrapping existing APIs into a Task based API, but the framework itself didn’t really adopt Task or Task<TResult> in any meaningful way.  The CTP shows that, going forward, this is changing. One of the three key new features coming in C# is actually a .NET Framework feature.  Nearly every asynchronous API in the .NET Framework has been wrapped into a new, Task-based method calls.  In the CTP, this is done via as external assembly (AsyncCtpLibrary.dll) which uses Extension Methods to wrap the existing APIs.  However, going forward, this will be handled directly within the Framework.  This will have a unifying effect throughout the .NET Framework.  This is the first building block of the new features for asynchronous programming: Going forward, all asynchronous operations will work via a method that returns Task or Task<TResult> The second key feature is the new async contextual keyword being added to the language.  The async keyword is used to declare an asynchronous function, which is a method that either returns void, a Task, or a Task<T>. Inside the asynchronous function, there must be at least one await expression.  This is a new C# keyword (await) that is used to automatically take a series of statements and break it up to potentially use discontinuous evaluation.  This is done by using await on any expression that evaluates to a Task or Task<T>. For example, suppose we want to download a webpage as a string.  There is a new method added to WebClient: Task<string> WebClient.DownloadStringTaskAsync(Uri).  Since this returns a Task<string> we can use it within an asynchronous function.  Suppose, for example, that we wanted to do something similar to my asynchronous Task example – download a web page asynchronously and check to see if it supports XHTML 1.0, then report this into a TextBox.  This could be done like so: private async void button1_Click(object sender, RoutedEventArgs e) { string url = "http://reedcopsey.com"; string content = await new WebClient().DownloadStringTaskAsync(url); this.textBox1.Text = string.Format("Page {0} supports XHTML 1.0: {1}", url, content.Contains("XHTML 1.0")); } .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; } Let’s walk through what’s happening here, step by step.  By adding the async contextual keyword to the method definition, we are able to use the await keyword on our WebClient.DownloadStringTaskAsync method call. When the user clicks this button, the new method (Task<string> WebClient.DownloadStringTaskAsync(string)) is called, which returns a Task<string>.  By adding the await keyword, the runtime will call this method that returns Task<string>, and execution will return to the caller at this point.  This means that our UI is not blocked while the webpage is downloaded.  Instead, the UI thread will “await” at this point, and let the WebClient do it’s thing asynchronously. When the WebClient finishes downloading the string, the user interface’s synchronization context will automatically be used to “pick up” where it left off, and the Task<string> returned from DownloadStringTaskAsync is automatically unwrapped and set into the content variable.  At this point, we can use that and set our text box content. There are a couple of key points here: Asynchronous functions are declared with the async keyword, and contain one or more await expressions In addition to the obvious benefits of shorter, simpler code – there are some subtle but tremendous benefits in this approach.  When the execution of this asynchronous function continues after the first await statement, the initial synchronization context is used to continue the execution of this function.  That means that we don’t have to explicitly marshal the call that sets textbox1.Text back to the UI thread – it’s handled automatically by the language and framework!  Exception handling around asynchronous method calls also just works. I’d recommend every C# developer take a look at the documentation on the new Asynchronous Programming for C# and Visual Basic page, download the Visual Studio Async CTP, and try it out.

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• Install the Ajax Control Toolkit from NuGet

  - by Stephen Walther

  The Ajax Control Toolkit is now available from NuGet. This makes it super easy to add the latest version of the Ajax Control Toolkit to any Web Forms application. If you haven’t used NuGet yet, then you are missing out on a great tool which you can use with Visual Studio to add new features to an application. You can use NuGet with both ASP.NET MVC and ASP.NET Web Forms applications. NuGet is compatible with both Websites and Web Applications and it works with both C# and VB.NET applications. For example, I habitually use NuGet to add the latest version of ELMAH, Entity Framework, jQuery, jQuery UI, and jQuery Templates to applications that I create. To download NuGet, visit the NuGet website at: http://NuGet.org Imagine, for example, that you want to take advantage of the Ajax Control Toolkit RoundedCorners extender to create cross-browser compatible rounded corners in a Web Forms application. Follow these steps. Right click on your project in the Solution Explorer window and select the option Add Library Package Reference. In the Add Library Package Reference dialog, select the Online tab and enter AjaxControlToolkit in the search box: Click the Install button and the latest version of the Ajax Control Toolkit will be installed. Installing the Ajax Control Toolkit makes several modifications to your application. First, a reference to the Ajax Control Toolkit is added to your application. In a Web Application Project, you can see the new reference in the References folder: Installing the Ajax Control Toolkit NuGet package also updates your Web.config file. The tag prefix ajaxToolkit is registered so that you can easily use Ajax Control Toolkit controls within any page without adding a @Register directive to the page. <configuration> <system.web> <compilation debug="true" targetFramework="4.0" /> <pages> <controls> <add tagPrefix="ajaxToolkit" assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" /> </controls> </pages> </system.web> </configuration> You should do a rebuild of your application by selecting the Visual Studio menu option Build, Rebuild Solution so that Visual Studio picks up on the new controls (You won’t get Intellisense for the Ajax Control Toolkit controls until you do a build). After you add the Ajax Control Toolkit to your application, you can start using any of the 40 Ajax Control Toolkit controls in your application (see http://www.asp.net/ajax/ajaxcontroltoolkit/samples/ for a reference for the controls). <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="WebApplication1.WebForm1" %> <!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 runat="server"> <title>Rounded Corners</title> <style type="text/css"> #pnl1 { background-color: gray; width: 200px; color:White; font: 14pt Verdana; } #pnl1_contents { padding: 10px; } </style> </head> <body> <form id="form1" runat="server"> <div> <asp:Panel ID="pnl1" runat="server"> <div id="pnl1_contents"> I have rounded corners! </div> </asp:Panel> <ajaxToolkit:ToolkitScriptManager ID="sm1" runat="server" /> <ajaxToolkit:RoundedCornersExtender TargetControlID="pnl1" runat="server" /> </div> </form> </body> </html> The page contains the following three controls: Panel – The Panel control named pnl1 contains the content which appears with rounded corners. ToolkitScriptManager – Every page which uses the Ajax Control Toolkit must contain a single ToolkitScriptManager. The ToolkitScriptManager loads all of the JavaScript files used by the Ajax Control Toolkit. RoundedCornersExtender – This Ajax Control Toolkit extender targets the Panel control. It makes the Panel control appear with rounded corners. You can control the “roundiness” of the corners by modifying the Radius property. Notice that you get Intellisense when typing the Ajax Control Toolkit tags. As soon as you type <ajaxToolkit, all of the available Ajax Control Toolkit controls appear: When you open the page in a browser, then the contents of the Panel appears with rounded corners. The advantage of using the RoundedCorners extender is that it is cross-browser compatible. It works great with Internet Explorer, Opera, Firefox, Chrome, and Safari even though different browsers implement rounded corners in different ways. The RoundedCorners extender even works with an ancient browser such as Internet Explorer 6. Getting the Latest Version of the Ajax Control Toolkit The Ajax Control Toolkit continues to evolve at a rapid pace. We are hard at work at fixing bugs and adding new features to the project. We plan to have a new release of the Ajax Control Toolkit each month. The easiest way to get the latest version of the Ajax Control Toolkit is to use NuGet. You can open the NuGet Add Library Package Reference dialog at any time to update the Ajax Control Toolkit to the latest version.

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• Parallelism in .NET – Part 13, Introducing the Task class

  - by Reed

  Once we’ve used a task-based decomposition to decompose a problem, we need a clean abstraction usable to implement the resulting decomposition.  Given that task decomposition is founded upon defining discrete tasks, .NET 4 has introduced a new API for dealing with task related issues, the aptly named Task class. The Task class is a wrapper for a delegate representing a single, discrete task within your decomposition.  We will go into various methods of construction for tasks later, but, when reduced to its fundamentals, an instance of a Task is nothing more than a wrapper around a delegate with some utility functionality added.  In order to fully understand the Task class within the new Task Parallel Library, it is important to realize that a task really is just a delegate – nothing more.  In particular, note that I never mentioned threading or parallelism in my description of a Task.  Although the Task class exists in the new System.Threading.Tasks namespace: Tasks are not directly related to threads or multithreading. Of course, Task instances will typically be used in our implementation of concurrency within an application, but the Task class itself does not provide the concurrency used.  The Task API supports using Tasks in an entirely single threaded, synchronous manner. Tasks are very much like standard delegates.  You can execute a task synchronously via Task.RunSynchronously(), or you can use Task.Start() to schedule a task to run, typically asynchronously.  This is very similar to using delegate.Invoke to execute a delegate synchronously, or using delegate.BeginInvoke to execute it asynchronously. The Task class adds some nice functionality on top of a standard delegate which improves usability in both synchronous and multithreaded environments. The first addition provided by Task is a means of handling cancellation via the new unified cancellation mechanism of .NET 4.  If the wrapped delegate within a Task raises an OperationCanceledException during it’s operation, which is typically generated via calling ThrowIfCancellationRequested on a CancellationToken, or if the CancellationToken used to construct a Task instance is flagged as canceled, the Task’s IsCanceled property will be set to true automatically.  This provides a clean way to determine whether a Task has been canceled, often without requiring specific exception handling. Tasks also provide a clean API which can be used for waiting on a task.  Although the Task class explicitly implements IAsyncResult, Tasks provide a nicer usage model than the traditional .NET Asynchronous Programming Model.  Instead of needing to track an IAsyncResult handle, you can just directly call Task.Wait() to block until a Task has completed.  Overloads exist for providing a timeout, a CancellationToken, or both to prevent waiting indefinitely.  In addition, the Task class provides static methods for waiting on multiple tasks – Task.WaitAll and Task.WaitAny, again with overloads providing time out options.  This provides a very simple, clean API for waiting on single or multiple tasks. Finally, Tasks provide a much nicer model for Exception handling.  If the delegate wrapped within a Task raises an exception, the exception will automatically get wrapped into an AggregateException and exposed via the Task.Exception property.  This exception is stored with the Task directly, and does not tear down the application.  Later, when Task.Wait() (or Task.WaitAll or Task.WaitAny) is called on this task, an AggregateException will be raised at that point if any of the tasks raised an exception.  For example, suppose we have the following code: Task taskOne = new Task( () => { throw new ApplicationException("Random Exception!"); }); Task taskTwo = new Task( () => { throw new ArgumentException("Different exception here"); }); // Start the tasks taskOne.Start(); taskTwo.Start(); try { Task.WaitAll(new[] { taskOne, taskTwo }); } catch (AggregateException e) { Console.WriteLine(e.InnerExceptions.Count); foreach (var inner in e.InnerExceptions) Console.WriteLine(inner.Message); } .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; } Here, our routine will print: 2 Different exception here Random Exception! Note that we had two separate tasks, each of which raised two distinctly different types of exceptions.  We can handle this cleanly, with very little code, in a much nicer manner than the Asynchronous Programming API.  We no longer need to handle TargetInvocationException or worry about implementing the Event-based Asynchronous Pattern properly by setting the AsyncCompletedEventArgs.Error property.  Instead, we just raise our exception as normal, and handle AggregateException in a single location in our calling code.

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• Parallelism in .NET – Part 16, Creating Tasks via a TaskFactory

  - by Reed

  The Task class in the Task Parallel Library supplies a large set of features.  However, when creating the task, and assigning it to a TaskScheduler, and starting the Task, there are quite a few steps involved.  This gets even more cumbersome when multiple tasks are involved.  Each task must be constructed, duplicating any options required, then started individually, potentially on a specific scheduler.  At first glance, this makes the new Task class seem like more work than ThreadPool.QueueUserWorkItem in .NET 3.5. In order to simplify this process, and make Tasks simple to use in simple cases, without sacrificing their power and flexibility, the Task Parallel Library added a new class: TaskFactory. The TaskFactory class is intended to “Provide support for creating and scheduling Task objects.”  Its entire purpose is to simplify development when working with Task instances.  The Task class provides access to the default TaskFactory via the Task.Factory static property.  By default, TaskFactory uses the default TaskScheduler to schedule tasks on a ThreadPool thread.  By using Task.Factory, we can automatically create and start a task in a single “fire and forget” manner, similar to how we did with ThreadPool.QueueUserWorkItem: Task.Factory.StartNew(() => this.ExecuteBackgroundWork(myData) ); .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; } This provides us with the same level of simplicity we had with ThreadPool.QueueUserWorkItem, but even more power.  For example, we can now easily wait on the task: // Start our task on a background thread var task = Task.Factory.StartNew(() => this.ExecuteBackgroundWork(myData) ); // Do other work on the main thread, // while the task above executes in the background this.ExecuteWorkSynchronously(); // Wait for the background task to finish task.Wait(); TaskFactory simplifies creation and startup of simple background tasks dramatically. In addition to using the default TaskFactory, it’s often useful to construct a custom TaskFactory.  The TaskFactory class includes an entire set of constructors which allow you to specify the default configuration for every Task instance created by that factory.  This is particularly useful when using a custom TaskScheduler.  For example, look at the sample code for starting a task on the UI thread in Part 15: // Given the following, constructed on the UI thread // TaskScheduler uiScheduler = TaskScheduler.FromCurrentSynchronizationContext(); // When inside a background task, we can do string status = GetUpdatedStatus(); (new Task(() => { statusLabel.Text = status; })) .Start(uiScheduler); This is actually quite a bit more complicated than necessary.  When we create the uiScheduler instance, we can use that to construct a TaskFactory that will automatically schedule tasks on the UI thread.  To do that, we’d create the following on our main thread, prior to constructing our background tasks: // Construct a task scheduler from the current SynchronizationContext (UI thread) var uiScheduler = TaskScheduler.FromCurrentSynchronizationContext(); // Construct a new TaskFactory using our UI scheduler var uiTaskFactory = new TaskFactory(uiScheduler); If we do this, when we’re on a background thread, we can use this new TaskFactory to marshal a Task back onto the UI thread.  Our previous code simplifies to: // When inside a background task, we can do string status = GetUpdatedStatus(); // Update our UI uiTaskFactory.StartNew( () => statusLabel.Text = status); Notice how much simpler this becomes!  By taking advantage of the convenience provided by a custom TaskFactory, we can now marshal to set data on the UI thread in a single, clear line of code!

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• 6 Interesting Facts About NASA’s Mars Rover ‘Curiosity’

  - by Gopinath

  Humans quest for exploring the surrounding planets to see whether we can live there or not is taking new shape today. NASA’s Mars probing robot, Curiosity, blasted off today on its 9 months journey to reach Mars and explore it for the possibilities of life there. Scientist says that Curiosity is one most advanced rover ever launched to probe life on other planets. Here is the launch video and some analysis by a news reporter Lets look at the 6 interesting facts about the mission 1. It’s as big as a car Curiosity is the biggest ever rover ever launched by NASA to probe life on outer planets. It’s as big as a car and almost double the size of its predecessor rover Spirit. The length of Curiosity is around 9 feet 10 inches(3 meters), width is 9 feet 1 inch (2.8 meters) and height is 7 feet (2.1 meters). 2. Powered by Plutonium – Lasts 24×7 for 23 months The earlier missions of NASA to explore Mars are powered by Solar power and that hindered capabilities of the rovers to move around when the Sun is hiding. Due to dependency of Sun the earlier rovers were not able to traverse the places where there is no Sun light. Curiosity on the other hand is equipped with a radioisotope power system that generates electricity from the heat emitted by plutonium’s radioactive decay. The plutonium weighs around 10 pounds and can generate power required for operating the rover close to 23 weeks. The best part of the new power system is, Curiosity can roam around in darkness, light and all year around. 3. Rocket powered backpack for a science fiction style landing The Curiosity is so heavy that NASA could not use parachute and balloons to air-drop the rover on the surface of Mars like it’s previous missions. They are trying out a new science fiction style air-dropping mechanism that is similar to sky crane heavy-lift helicopter. The landing of the rover begins first with entry into the Mars atmosphere protected by a heat shield. At about 6 miles to the surface, the heat shield is jettisoned and a parachute is deployed to glide the rover smoothly. When the rover touches 3 miles above the surface, the parachute is jettisoned and the eight motors rocket backpack is used for a smooth and impact free landing as shown in the image. Here is an animation created by NASA on the landing sequence. If you are interested in getting more detailed information about the landing process check this landing sequence picture available on NASA website 4. Equipped with Star Wars style laser gun Hollywood movie directors and novelist always imagined aliens coming to earth with spaceships full of laser guns and blasting the objects which comes on their way. With Curiosity the equations are going to change. It has a powerful laser gun equipped in one of it’s arms to beam laser on rocks to vaporize them. This is not part of any assault mission Curiosity is expected to carry out, the laser gun is will be used to carry out experiments to detect life and understand nature. 5. Most sophisticated laboratory powered by 10 instruments Around 10 state of art instruments are part of Curiosity rover and the these 10 instruments form a most advanced rover based lab ever built by NASA. There are instruments to cut through rocks to examine them and other instruments will search for organic compounds. Mounted cameras can study targets from a distance, arm mounted instruments can study the targets they touch. Microscopic lens attached to the arm can see and magnify tiny objects as tiny as 12.5 micro meters. 6. Rover Carrying 1.24 million names etched on silicon Early June 2009 NASA launched a campaign called “Send Your Name to Mars” and around 1.24 million people registered their names through NASA’s website. All those 1.24 million names are etched on Silicon chips mounted onto Curiosity’s deck. If you had registered your name in the campaign may be your name is going to reach Mars soon. Curiosity On Web If you wish to follow the mission here are few links to help you NASA’s Curiosity Web Page Follow Curiosity on Facebook Follow @MarsCuriosity on Twitter Artistic Gallery Image of Mars Rover Curiosity A printable sheet of Curiosity Mission [pdf] Images credit: NASA This article titled,6 Interesting Facts About NASA’s Mars Rover ‘Curiosity’, was originally published at Tech Dreams. Grab our rss feed or fan us on Facebook to get updates from us.

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• Tweaking a few URL validation settings on ASP.NET v4.0

  - by Carlyle Dacosta

  ASP.NET has a few default settings for URLs out of the box. These can be configured quite easily in the web.config file within the  <system.web>/<httpRuntime> configuration section. Some of these are: <httpRuntime maxUrlLength=”<number here>”. This number should be an integer value (defaults to 260 characters). The value must be greater than or equal to zero, though obviously small values will lead to an un-useable website. This attribute gates the length of the Url without query string. <httpRuntime maxQueryStringLength=”<number here>”. This number should be an integer value (defaults to 2048 characters). The value must be greater than or equal to zero, though obviously small values will lead to an un-useable website. <httpRuntime requestPathInvalidCharacters=”List of characters you need included in ASP.NETs validation checks”. By default the characters are “<,>,*,%,&,:,\,?”. However once can easily change this by setting by modifying web.config. Remember, these characters can be specified in a variety of formats. For example, I want the character ‘!’ to be included in ASP.NETs URL validation logic. So I set the following: <httpRuntime requestPathInvalidCharacters=”<,>,*,%,&,:,\,?,!”. A character could also be specified in its xml encoded form. ‘&lt;;’ would mean the ‘<’ sign). I could specify the ‘!’ in its xml encoded unicode format such as requestPathInvalidCharacters=”<,>,*,%,&,:,\,?,$#x0021;” or I could specify it in its unicode encoded form or in the “<,>,*,%,&,:,\,?,%u0021” format. The following settings can be applied at Root Web.Config level, App Web.config level, Folder level or within a location tag: <location path="some path here"> <system.web> <httpRuntime maxUrlLength="" maxQueryStringLength="" requestPathInvalidChars="" .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; } If any of the above settings fail request validation, an Http 400 “Bad Request” HttpException is thrown. These can be easily handled on the Application_Error handler on Global.asax.   Also, a new attribute in <httpRuntime /> called “relaxedUrlToFileSystemMapping” has been added with a default of false. <httpRuntime … relaxedUrlToFileSystemMapping="true|false" /> When the relaxedUrlToFileSystemMapping attribute is set to false inbound Urls still need to be valid NTFS file paths. For example Urls (sans query string) need to be less than 260 characters; no path segment within a Url can use old-style DOS device names (LPT1, COM1, etc…); Urls must be valid Windows file paths. A url like “http://digg.com/http://cnn.com” should work with this attribute set to true (of course a few characters will need to be unblocked by removing them from requestPathInvalidCharacters="" above). Managed configuration for non-NTFS-compliant Urls is determined from the first valid configuration path found when walking up the path segments of the Url. For example, if the request Url is "/foo/bar/baz/<blah>data</blah>", and there is a web.config in the "/foo/bar" directory, then the managed configuration for the request comes from merging the configuration hierarchy to include the web.config from "/foo/bar". The value of the public property HttpRequest.PhysicalPath is set to [physical file path of the application root] + "REQUEST_URL_IS_NOT_A_VALID_FILESYSTEM_PATH". For example, given a request Url like "/foo/bar/baz/<blah>data</blah>", where the application root is "/foo/bar" and the physical file path for that root is "c:\inetpub\wwwroot\foo\bar", then PhysicalPath would be "c:\inetpub\wwwroot\foo\bar\ REQUEST_URL_IS_NOT_A_VALID_FILESYSTEM_PATH". Carl Dacosta ASP.NET QA Team

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• Analytic functions – they’re not aggregates

  - by Rob Farley

  SQL 2012 brings us a bunch of new analytic functions, together with enhancements to the OVER clause. People who have known me over the years will remember that I’m a big fan of the OVER clause and the types of things that it brings us when applied to aggregate functions, as well as the ranking functions that it enables. The OVER clause was introduced in SQL Server 2005, and remained frustratingly unchanged until SQL Server 2012. This post is going to look at a particular aspect of the analytic functions though (not the enhancements to the OVER clause). When I give presentations about the analytic functions around Australia as part of the tour of SQL Saturdays (starting in Brisbane this Thursday), and in Chicago next month, I’ll make sure it’s sufficiently well described. But for this post – I’m going to skip that and assume you get it. The analytic functions introduced in SQL 2012 seem to come in pairs – FIRST_VALUE and LAST_VALUE, LAG and LEAD, CUME_DIST and PERCENT_RANK, PERCENTILE_CONT and PERCENTILE_DISC. Perhaps frustratingly, they take slightly different forms as well. The ones I want to look at now are FIRST_VALUE and LAST_VALUE, and PERCENTILE_CONT and PERCENTILE_DISC. The reason I’m pulling this ones out is that they always produce the same result within their partitions (if you’re applying them to the whole partition). Consider the following query: SELECT     YEAR(OrderDate),     FIRST_VALUE(TotalDue)         OVER (PARTITION BY YEAR(OrderDate)               ORDER BY OrderDate, SalesOrderID               RANGE BETWEEN UNBOUNDED PRECEDING                         AND UNBOUNDED FOLLOWING),     LAST_VALUE(TotalDue)         OVER (PARTITION BY YEAR(OrderDate)               ORDER BY OrderDate, SalesOrderID               RANGE BETWEEN UNBOUNDED PRECEDING                         AND UNBOUNDED FOLLOWING),     PERCENTILE_CONT(0.95)         WITHIN GROUP (ORDER BY TotalDue)         OVER (PARTITION BY YEAR(OrderDate)),     PERCENTILE_DISC(0.95)         WITHIN GROUP (ORDER BY TotalDue)         OVER (PARTITION BY YEAR(OrderDate)) FROM Sales.SalesOrderHeader ; This is designed to get the TotalDue for the first order of the year, the last order of the year, and also the 95% percentile, using both the continuous and discrete methods (‘discrete’ means it picks the closest one from the values available – ‘continuous’ means it will happily use something between, similar to what you would do for a traditional median of four values). I’m sure you can imagine the results – a different value for each field, but within each year, all the rows the same. Notice that I’m not grouping by the year. Nor am I filtering. This query gives us a result for every row in the SalesOrderHeader table – 31465 in this case (using the original AdventureWorks that dates back to the SQL 2005 days). The RANGE BETWEEN bit in FIRST_VALUE and LAST_VALUE is needed to make sure that we’re considering all the rows available. If we don’t specify that, it assumes we only mean “RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW”, which means that LAST_VALUE ends up being the row we’re looking at. At this point you might think about other environments such as Access or Reporting Services, and remember aggregate functions like FIRST. We really should be able to do something like: SELECT     YEAR(OrderDate),     FIRST_VALUE(TotalDue)         OVER (PARTITION BY YEAR(OrderDate)               ORDER BY OrderDate, SalesOrderID               RANGE BETWEEN UNBOUNDED PRECEDING                         AND UNBOUNDED FOLLOWING) FROM Sales.SalesOrderHeader GROUP BY YEAR(OrderDate) ; But you can’t. You get that age-old error: Msg 8120, Level 16, State 1, Line 5 Column 'Sales.SalesOrderHeader.OrderDate' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause. Msg 8120, Level 16, State 1, Line 5 Column 'Sales.SalesOrderHeader.SalesOrderID' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause. Hmm. You see, FIRST_VALUE isn’t an aggregate function. None of these analytic functions are. There are too many things involved for SQL to realise that the values produced might be identical within the group. Furthermore, you can’t even surround it in a MAX. Then you get a different error, telling you that you can’t use windowed functions in the context of an aggregate. And so we end up grouping by doing a DISTINCT. SELECT DISTINCT     YEAR(OrderDate),         FIRST_VALUE(TotalDue)              OVER (PARTITION BY YEAR(OrderDate)                   ORDER BY OrderDate, SalesOrderID                   RANGE BETWEEN UNBOUNDED PRECEDING                             AND UNBOUNDED FOLLOWING),         LAST_VALUE(TotalDue)             OVER (PARTITION BY YEAR(OrderDate)                   ORDER BY OrderDate, SalesOrderID                   RANGE BETWEEN UNBOUNDED PRECEDING                             AND UNBOUNDED FOLLOWING),     PERCENTILE_CONT(0.95)          WITHIN GROUP (ORDER BY TotalDue)         OVER (PARTITION BY YEAR(OrderDate)),     PERCENTILE_DISC(0.95)         WITHIN GROUP (ORDER BY TotalDue)         OVER (PARTITION BY YEAR(OrderDate)) FROM Sales.SalesOrderHeader ; I’m sorry. It’s just the way it goes. Hopefully it’ll change the future, but for now, it’s what you’ll have to do. If we look in the execution plan, we see that it’s incredibly ugly, and actually works out the results of these analytic functions for all 31465 rows, finally performing the distinct operation to convert it into the four rows we get in the results. You might be able to achieve a better plan using things like TOP, or the kind of calculation that I used in http://sqlblog.com/blogs/rob_farley/archive/2011/08/23/t-sql-thoughts-about-the-95th-percentile.aspx (which is how PERCENTILE_CONT works), but it’s definitely convenient to use these functions, and in time, I’m sure we’ll see good improvements in the way that they are implemented. Oh, and this post should be good for fellow SQL Server MVP Nigel Sammy’s T-SQL Tuesday this month.

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• Thursday Community Keynote: "By the Community, For the Community"

  - by Janice J. Heiss

  Sharat Chander, JavaOne Community Chairperson, began Thursday's Community Keynote. As part of the morning’s theme of "By the Community, For the Community," Chander noted that 60% of the material at the 2012 JavaOne conference was presented by Java Community members. "So next year, when the call for papers starts, put-in your submissions," he urged.From there, Gary Frost, Principal Member of Technical Staff, AMD, expanded upon Sunday's Strategy Keynote exploration of Project Sumatra, an OpenJDK project targeted at bringing Java to heterogeneous computing platforms (which combine the CPU and the parallel processor of the GPU into a single piece of silicon). Sumatra entails enhancing the JVM to make maximum use of these advanced platforms. Within this development space, AMD created the Aparapi API, which converts Java bytecode into OpenCL for execution on such GPU devices. The Aparapi API was open sourced in September 2011.Whether it was zooming-in on a Mandelbrot set, "the game of life," or a swarm of 10,000 Dukes in a space-bound gravitational dance, Frost's demos, using an Aparapi/OpenCL implementation, produced stunningly faster display results. He indicated that the Java 9 timeframe is where they see Project Sumatra coming to ultimate fruition, employing the Lamdas of Java 8.Returning to the theme of the keynote, Donald Smith, Director, Java Product Management, Oracle, explored a mind map graphic demonstrating the importance of Community in terms of fostering innovation. "It's the sharing and mixing of culture, the diversity, and the rapid prototyping," he said. Within this topic, Smith, brought up a panel of representatives from Cloudera, Eclipse, Eucalyptus, Perrone Robotics, and Twitter--ideal manifestations of community and innovation in the world of Java.Marten Mickos, CEO, Eucalyptus Systems, explored his company's open source cloud software platform, written in Java, and used by gaming companies, technology companies, media companies, and more. Chris Aniszczyk, Operations Engineering,Twitter, noted the importance of the JVM in terms of their multiple-language development environment. Mike Olson, CEO, Cloudera, described his company's Apache Hadoop-based software, support, and training. Mike Milinkovich, Executive Director, Eclipse Foundation, noted that they have about 270 tools projects at Eclipse, with 267 of them written in Java. Milinkovich added that Eclipse will even be going into space in 2013, as part of the control software on various experiments aboard the International Space Station. Lastly, Paul Perrone, CEO, Perrone Robotics, detailed his company's robotics and automation software platform built 100% on Java, including Java SE and Java ME--"on rat, to cat, to elephant-sized systems." Milinkovic noted that communities are by nature so good at innovation because of their very openness--"The more open you make your innovation process, the more ideas are challenged, and the more developers are focused on justifying their choices all the way through the process."From there, Georges Saab, VP Development Java SE OpenJDK, continued the topic of innovation and helping the Java Community to "Make the Future Java." Martijn Verburg, representing the London Java Community (winner of a Duke's Choice Award 2012 for their activity in OpenJDK and JCP), soon joined Saab onstage. Verburg detailed the LJC's "Adopt a JSR" program--"to get day-to-day developers more involved in the innovation that's happening around them."  From its London launching pad, the innovative program has spread to Brazil, Morocco, Latvia, India, and more.Other active participants in the program joined Verburg onstage--Ben Evans, London Java Community; James Gough, Stackthread; Bruno Souza, SOUJava; Richard Warburton, jClarity; and Cecelia Borg, Oracle--OpenJDK Onboarding. Together, the group explored the goals and tasks inherent in the Adopt a JSR program--from organizing hack days (testing prototype implementations), to managing mailing lists and forums, to triaging issues, to evangelism—all with the goal of fostering greater community/developer involvement, but equally importantly, building better open standards. “Come join us, and make your ecosystem better!" urged Verburg.Paul Perrone returned to profile the latest in his company's robotics work around Java--including the AARDBOTS family of smaller robotic vehicles, running the Perrone MAX platform on top of the Java JVM. Perrone took his "Rumbles" four-wheeled robot out for a spin onstage--a roaming, ARM-based security-bot vehicle, complete with IR, ultrasonic, and "cliff" sensors (the latter, for the raised stage at JavaOne). As an ultimate window into the future of robotics, Perrone displayed a "head-set" controller--a sensor directed at the forehead to monitor brainwaves, for the someday-implementation of brain-to-robot control.Then, just when it seemed this might be the end of the day's futuristic offerings, a mystery voice from offstage pronounced "I've got some toys"--proving to be guest-visitor James Gosling, there to explore his cutting-edge work with Liquid Robotics. While most think of robots as something with wheels or arms or lasers, Gosling explained, the Liquid Robotics vehicle is an entirely new and innovative ocean-going 'bot. Looking like a floating surfboard, with an attached set of underwater wings, the autonomous devices roam the oceans using only the energy of ocean waves to propel them, and a single actuated rudder to steer. "We have to accomplish all guidance just by wiggling the rudder," Gosling said. The devices offer applications from self-installing weather buoy, to pollution monitoring station, to marine mammal monitoring device, to climate change data gathering, to even ocean life genomic sampling. The early versions of the vehicle used C code on very tiny industrial micro controllers, where they had to "count the bytes one at a time."  But the latest generation vehicles, which just hit the water a week or so ago, employ an ARM processor running Linux and the ARM version of JDK 7. Gosling explained that vehicle communication from remote locations is achieved via the Iridium satellite network. But because of the costs of this communication path, the data must be sent in very small bursts--using SBD short burst data. "It costs $1/kb, so that rules everything in the software design,” said Gosling. “If you were trying to stream a Netflix video over this, it would cost a million dollars a movie. …We don't have a 'big data' problem," he quipped. There are currently about 150 Liquid Robotics vehicles out traversing the oceans. Gosling demonstrated real time satellite tracking of several vehicles currently at sea, noting that Java is actually particularly good at AI applications--due to the language having garbage collection, which facilitates complex data structures. To close-out his time onstage, Gosling of course participated in the ceremonial Java tee-shirt toss out to the audience…In parting, Chander passed the JavaOne Community Chairperson baton to Stephen Chin, Java Technology Evangelist, Oracle. Onstage in full motorcycle gear, Chin noted that he'll soon be touring Europe by motorcycle, meeting Java Community Members and streaming live via UStream--the ultimate manifestation of community and technology!  He also reminded attendees of the upcoming JavaOne Latin America 2012, São Paulo, Brazil (December 4-6, 2012), and stated that the CFP (call for papers) at the conference has been extended for one more week. "Remember, December is summer in Brazil!" Chin said.

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• ODI 12c - Parallel Table Load

  - by David Allan

  In this post we will look at the ODI 12c capability of parallel table load from the aspect of the mapping developer and the knowledge module developer - two quite different viewpoints. This is about parallel table loading which isn't to be confused with loading multiple targets per se. It supports the ability for ODI mappings to be executed concurrently especially if there is an overlap of the datastores that they access, so any temporary resources created may be uniquely constructed by ODI. Temporary objects can be anything basically - common examples are staging tables, indexes, views, directories - anything in the ETL to help the data integration flow do its job. In ODI 11g users found a few workarounds (such as changing the technology prefixes - see here) to build unique temporary names but it was more of a challenge in error cases. ODI 12c mappings by default operate exactly as they did in ODI 11g with respect to these temporary names (this is also true for upgraded interfaces and scenarios) but can be configured to support the uniqueness capabilities. We will look at this feature from two aspects; that of a mapping developer and that of a developer (of procedures or KMs). 1. Firstly as a Mapping Developer..... 1.1 Control when uniqueness is enabled A new property is available to set unique name generation on/off. When unique names have been enabled for a mapping, all temporary names used by the collection and integration objects will be generated using unique names. This property is presented as a check-box in the Property Inspector for a deployment specification. 1.2 Handle cleanup after successful execution Provided that all temporary objects that are created have a corresponding drop statement then all of the temporary objects should be removed during a successful execution. This should be the case with the KMs developed by Oracle. 1.3 Handle cleanup after unsuccessful execution If an execution failed in ODI 11g then temporary tables would have been left around and cleaned up in the subsequent run. In ODI 12c, KM tasks can now have a cleanup-type task which is executed even after a failure in the main tasks. These cleanup tasks will be executed even on failure if the property 'Remove Temporary Objects on Error' is set. If the agent was to crash and not be able to execute this task, then there is an ODI tool (OdiRemoveTemporaryObjects here) you can invoke to cleanup the tables - it supports date ranges and the like. That's all there is to it from the aspect of the mapping developer it's much, much simpler and straightforward. You can now execute the same mapping concurrently or execute many mappings using the same resource concurrently without worrying about conflict.  2. Secondly as a Procedure or KM Developer..... In the ODI Operator the executed code shows the actual name that is generated - you can also see the runtime code prior to execution (introduced in 11.1.1.7), for example below in the code type I selected 'Pre-executed Code' this lets you see the code about to be processed and you can also see the executed code (which is the default view). References to the collection (C$) and integration (I$) names will be automatically made unique by using the odiRef APIs - these objects will have unique names whenever concurrency has been enabled for a particular mapping deployment specification. It's also possible to use name uniqueness functions in procedures and your own KMs. 2.1 New uniqueness tags  You can also make your own temporary objects have unique names by explicitly including either %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG in the name passed to calls to the odiRef APIs. Such names would always include the unique tag regardless of the concurrency setting. To illustrate, let's look at the getObjectName() method. At <% expansion time, this API will append %UNIQUE_STEP_TAG to the object name for collection and integration tables. The name parameter passed to this API may contain  %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG. This API always generates to the <? version of getObjectName() At execution time this API will replace the unique tag macros with a string that is unique to the current execution scope. The returned name will conform to the name-length restriction for the target technology, and its pattern for the unique tag. Any necessary truncation will be performed against the initial name for the object and any other fixed text that may have been specified. Examples are:- <?=odiRef.getObjectName("L", "%COL_PRFEMP%UNIQUE_STEP_TAG", "D")?> SCOTT.C$_EABH7QI1BR1EQI3M76PG9SIMBQQ <?=odiRef.getObjectName("L", "EMP%UNIQUE_STEP_TAG_AE", "D")?> SCOTT.EMPAO96Q2JEKO0FTHQP77TMSAIOSR_ Methods which have this kind of support include getFrom, getTableName, getTable, getObjectShortName and getTemporaryIndex. There are APIs for retrieving this tag info also, the getInfo API has been extended with the following properties (the UNIQUE* properties can also be used in ODI procedures); UNIQUE_STEP_TAG - Returns the unique value for the current step scope, e.g. 5rvmd8hOIy7OU2o1FhsF61 Note that this will be a different value for each loop-iteration when the step is in a loop. UNIQUE_SESSION_TAG - Returns the unique value for the current session scope, e.g. 6N38vXLrgjwUwT5MseHHY9 IS_CONCURRENT - Returns info about the current mapping, will return 0 or 1 (only in % phase) GUID_SRC_SET - Returns the UUID for the current source set/execution unit (only in % phase) The getPop API has been extended with the IS_CONCURRENT property which returns info about an mapping, will return 0 or 1.  2.2 Additional APIs Some new APIs are provided including getFormattedName which will allow KM developers to construct a name from fixed-text or ODI symbols that can be optionally truncate to a max length and use a specific encoding for the unique tag. It has syntax getFormattedName(String pName[, String pTechnologyCode]) This API is available at both the % and the ? phase.  The format string can contain the ODI prefixes that are available for getObjectName(), e.g. %INT_PRF, %COL_PRF, %ERR_PRF, %IDX_PRF alongwith %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG. The latter tags will be expanded into a unique string according to the specified technology. Calls to this API within the same execution context are guaranteed to return the same unique name provided that the same parameters are passed to the call. e.g. <%=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG_AE", "ORACLE")%> <?=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG_AE", "ORACLE")?> C$_MY_TAB7wDiBe80vBog1auacS1xB_AE <?=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG.log", "FILE")?> C2_MY_TAB7wDiBe80vBog1auacS1xB.log 2.3 Name length generation  As part of name generation, the length of the generated name will be compared with the maximum length for the target technology and truncation may need to be applied. When a unique tag is included in the generated string it is important that uniqueness is not compromised by truncation of the unique tag. When a unique tag is NOT part of the generated name, the name will be truncated by removing characters from the end - this is the existing 11g algorithm. When a unique tag is included, the algorithm will first truncate the <postfix> and if necessary  the <prefix>. It is recommended that users will ensure there is sufficient uniqueness in the <prefix> section to ensure uniqueness of the final resultant name. SUMMARY To summarize, ODI 12c make it much simpler to utilize mappings in concurrent cases and provides APIs for helping developing any procedures or custom knowledge modules in such a way they can be used in highly concurrent, parallel scenarios. 

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• Monitor your Hard Drive’s Health with Acronis Drive Monitor

  - by Matthew Guay

  Are you worried that your computer’s hard drive could die without any warning?  Here’s how you can keep tabs on it and get the first warning signs of potential problems before you actually lose your critical data. Hard drive failures are one of the most common ways people lose important data from their computers.  As more of our memories and important documents are stored digitally, a hard drive failure can mean the loss of years of work.  Acronis Drive Monitor helps you avert these disasters by warning you at the first signs your hard drive may be having trouble.  It monitors many indicators, including heat, read/write errors, total lifespan, and more. It then notifies you via a taskbar popup or email that problems have been detected.  This early warning lets you know ahead of time that you may need to purchase a new hard drive and migrate your data before it’s too late. Getting Started Head over to the Acronis site to download Drive Monitor (link below).  You’ll need to enter your name and email, and then you can download this free tool. Also, note that the download page may ask if you want to include a trial of their for-pay backup program.  If you wish to simply install the Drive Monitor utility, click Continue without adding. Run the installer when the download is finished.  Follow the prompts and install as normal. Once it’s installed, you can quickly get an overview of your hard drives’ health.  Note that it shows 3 categories: Disk problems, Acronis backup, and Critical Events.  On our computer, we had Seagate DiskWizard, an image backup utility based on Acronis Backup, installed, and Acronis detected it. Drive Monitor stays running in your tray even when the application window is closed.  It will keep monitoring your hard drives, and will alert you if there’s a problem. Find Detailed Information About Your Hard Drives Acronis’ simple interface lets you quickly see an overview of how the drives on your computer are performing.  If you’d like more information, click the link under the description.  Here we see that one of our drives have overheated, so click Show disks to get more information. Now you can select each of your drives and see more information about them.  From the Disk overview tab that opens by default, we see that our drive is being monitored, has been running for a total of 368 days, and that it’s health is good.  However, it is running at 113F, which is over the recommended max of 107F.   The S.M.A.R.T. parameters tab gives us more detailed information about our drive.  Most users wouldn’t know what an accepted value would be, so it also shows the status.  If the value is within the accepted parameters, it will report OK; otherwise, it will show that has a problem in this area. One very interesting piece of information we can see is the total number of Power-On Hours, Start/Stop Count, and Power Cycle Count.  These could be useful indicators to check if you’re considering purchasing a second hand computer.  Simply load this program, and you’ll get a better view of how long it’s been in use. Finally, the Events tab shows each time the program gave a warning.  We can see that our drive, which had been acting flaky already, is routinely overheating even when our other hard drive was running in normal temperature ranges. Monitor Acronis Backups And Critical Errors In addition to monitoring critical stats of your hard drives, Acronis Drive Monitor also keeps up with the status of your backup software and critical events reported by Windows.  You can access these from the front page, or via the links on the left hand sidebar.  If you have any edition of any Acronis Backup product installed, it will show that it was detected.  Note that it can only monitor the backup status of the newest versions of Acronis Backup and True Image. If no Acronis backup software was installed, it will show a warning that the drive may be unprotected and will give you a link to download Acronis backup software.   If you have another backup utility installed that you wish to monitor yourself, click Configure backup monitoring, and then disable monitoring on the drives you’re monitoring yourself. Finally, you can view any detected Critical events from the Critical events tab on the left. Get Emailed When There’s a Problem One of Drive Monitor’s best features is the ability to send you an email whenever there’s a problem.  Since this program can run on any version of Windows, including the Server and Home Server editions, you can use this feature to stay on top of your hard drives’ health even when you’re not nearby.  To set this up, click Options in the top left corner. Select Alerts on the left, and then click the Change settings link to setup your email account. Enter the email address which you wish to receive alerts, and a name for the program.  Then, enter the outgoing mail server settings for your email.  If you have a Gmail account, enter the following information: Outgoing mail server (SMTP): smtp.gmail.com Port: 587 Username and Password: Your gmail address and password Check the Use encryption box, and then select TLS from the encryption options.   It will now send a test message to your email account, so check and make sure it sent ok. Now you can choose to have the program automatically email you when warnings and critical alerts appear, and also to have it send regular disk status reports.   Conclusion Whether you’ve got a brand new hard drive or one that’s seen better days, knowing the real health of your it is one of the best ways to be prepared before disaster strikes.  It’s no substitute for regular backups, but can help you avert problems.  Acronis Drive Monitor is a nice tool for this, and although we wish it wasn’t so centered around their backup offerings, we still found it a nice tool. Link Download Acronis Drive Monitor (registration required) Similar Articles Productive Geek Tips Quick Tip: Change Monitor Timeout From Command LineAnalyze and Manage Hard Drive Space with WinDirStatMonitor CPU, Memory, and Disk IO In Windows 7 with Taskbar MetersDefrag Multiple Hard Drives At Once In WindowsFind Your Missing USB Drive on Windows XP TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips HippoRemote Pro 2.2 Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Windows 7’s WordPad is Actually Good Greate Image Viewing and Management with Zoner Photo Studio Free Windows Media Player Plus! – Cool WMP Enhancer Get Your Team’s World Cup Schedule In Google Calendar Backup Drivers With Driver Magician TubeSort: YouTube Playlist Organizer

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• Start a Mapping or Process Flow from OWB Browser

  - by Dong Ruirong

  Basically, we start a Mapping or Process Flow from Oracle Warehouse Builder (OWB) Design Client. But actually we can also start a Mapping or Process Flow from OWB Browser. This paper will introduce the Start Report first and then introduce how to start/rerun a Mapping or Process Flow from OWB Browser. Start Report Start Report is used to start an execution of a Mapping or Process Flow. So there are two kinds of Start Report: Mapping Start Report (See Figure 1) and Process Flow Start Report (See Figure 2). Start Report shows the Mapping or Process Flow identification properties, including latest deployment and latest execution, lists all execution parameters for the Mapping or Process Flow, which were specified by the latest deployment, and assigns parameter default values from the latest deployment specification. You can do a couple of things from Start Report: Sort execution parameters on name, category. Table 1 lists all parameters of a Mapping. Table 2 lists all parameters of a Process Flow. Change values of any input parameter where permitted. For some parameters, selection lists are provided. For example, Mapping’s parameter Audit Level has a selection list. Reset all parameter settings to their default values. Apply basic validation to parameter values before starting an execution. Start the Mapping or Process Flow, which means it is executed immediately. Navigate to Deployment Report for latest deployment details of the Mapping or Process Flow. Navigate to Execution Job Report for latest execution of current Mapping or Process Flow Link to on-link help Warehouse Report Page, Deployment Report, Execution Report, Execution Schedule Report and Execution Summary Report. Figure 1 Mapping Start Report Table 1 Execution Parameters and default values for a Mapping Category Name Mode Input Value System Audit Level In Error Details System Bulk Size In 1000 System Commit Frequency In 1000 System EXECUTE_RESUME_TASK In FALSE System FORCE_RESUME_OPTION In FALSE System Max No of Errors In 50 System NUMBER_OF_TIMES_TO_RETRY In 2 System Operating Mode In Set Based Fail Over to Row Based System PARALLEL_LEVEL In 0 System Procedure Name In main System Purge Group In WB Figure 2 Process Flow Start Report Table 2 Execution Parameters and default values for a Process Flow Category Name Mode Input Value System EVAL_LOCATION In   System Item Key In-Out   System Item Type In PFPKG_1 Start a Mapping or Process Flow To navigate to Start Report, it’s better to login OWB Browser with Control Center option; if not, after logging in OWB Browser, go to Control Center first. Then you can follow the ways introduced in this section to navigate to Start Report. One more thing you need to pay attention to is that you are not allowed to deploy any Mappings and Process Flows from OWB Browser as it’s not supported. So it’s necessary to deploy the Mappings and Process Flows first before starting them from OWB Browser. If you have deployed a Mapping or Process Flow but have not started it, please navigate from Object Summary Report or Deployment Schedule Report to Start Report. 1. Navigating from Object Summary Report to Start Report Open the Object Summary Report to see all deployed Mappings and Process Flows. Click the Mapping Name or Process Flow Name link to see its Deployment Report. Select the Start link in the Available Reports tab for the given Mapping or Process Flow to display a Start Report for the Mapping or Process Flow. The execution parameters have the default deployment-time settings. Change any of the input parameter values as required. Click Start Execution button to execute the Mapping or Process Flow. 2. Navigating from Deployment Schedule Report to Start Report Open the Deployment Schedule Report to see deployment details of Mapping and Process Flow. Expand the project trees to find the deployed Mappings and Process Flows. Click the Mapping Name or Process Flow Name link to see its Deployment Report. Select the Start link in the Available Reports tab for the given Mapping or Process Flow to display a Start Report for the Mapping or Process Flow. The execution parameters have the default deployment-time settings. Change any of the input parameter values as required. Click Start Execution button to execute the Mapping or Process Flow. Re-run a Mapping or Process Flow If you have executed a Mapping or Process Flow, you can navigate from Object Summary Report, Deployment Schedule Report, Execution Summary Report or Execution Schedule Report to Start Report. 1. Navigating from the Execution Summary Report to Start Report Open the Execution Summary Report to see all execution jobs including Mapping jobs and Process Flow jobs. Click on the Mapping Name or Process Flow Name to see its Execution Report. Select the Start link in the Available Reports tab for the given Mapping or Process Flow to display a Start Report for the Mapping or Process Flow. The execution parameters have the default deployment-time settings. Change any of the input parameter values as required. Click Start Execution button to execute the Mapping or Process Flow. 2. Navigating from the Execution Schedule Report to Start Report Open the Execution Schedule Report to see list of all executions of Mapping and Process Flow. Click on the Mapping Name or Process Flow Name to see its Execution Report. Select the Start link in the Available Reports tab for the given Mapping or Process Flow to display a Start Report for the Mapping or Process Flow. The execution parameters have the default deployment-time settings. Change any of the input parameter values as required. Click Start Execution button to execute the Mapping or Process Flow. If the execution of a Mapping or Process Flow is successful, you will see this message from the Start Report: Start Execution request successful. (See Figure 3) Figure 3 Execution Result You can also confirm the execution of the Mapping or Process Flow by referring to Execution Report of the current Mapping or Process Flow by clicking the link in the Available Reports tab for the given Mapping or Process Flow. One new record of execution job details is added to Execution Report of the Mapping or Process Flow which shows the details of the execution such as Start Time, Elapsed Time, Status, the number of records selected, inserted, updated, deleted etc.

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• Building the Elusive Windows Phone Panorama Control

  When the Windows Phone 7 Developer SDK was released a couple of weeks ago at MIX10 many people noticed the SDK doesnt include a template for a Panorama control.   Here at Clarity we decided to build our own Panorama control for use in some of our prototypes and I figured I would share what we came up with. There have been a couple of implementations of the Panorama control making their way through the interwebs, but I didnt think any of them really nailed the experience that is shown in the simulation videos.   One of the key design principals in the UX Guide for Windows Phone 7 is the use of motion.  The WP7 OS is fairly stripped of extraneous design elements and makes heavy use of typography and motion to give users the necessary visual cues.  Subtle animations and wide layouts help give the user a sense of fluidity and consistency across the phone experience.  When building the panorama control I was fairly meticulous in recreating the motion as shown in the videos.  The effect that is shown in the application hubs of the phone is known as a Parallax Scrolling effect.  This this pseudo-3D technique has been around in the computer graphics world for quite some time. In essence, the background images move slower than foreground images, creating an illusion of depth in 2D.  Here is an example of the traditional use: http://www.mauriciostudio.com/.  One of the animation gems I've learned while building interactive software is the follow animation.  The premise is straightforward: instead of translating content 1:1 with the interaction point, let the content catch up to the mouse or finger.  The difference is subtle, but the impact on the smoothness of the interaction is huge.  That said, it became the foundation of how I achieved the effect shown below.   Source Code Available HERE Before I briefly describe the approach I took in creating this control..and Ill add some **asterisks ** to the code below as my coding skills arent up to snuff with the rest of my colleagues.  This code is meant to be an interpretation of the WP7 panorama control and is not intended to be used in a production application.  1.  Layout the XAML The UI consists of three main components :  The background image, the Title, and the Content.  You can imagine each  these UI Elements existing on their own plane with a corresponding Translate Transform to create the Parallax effect.  2.  Storyboards + Procedural Animations = Sexy As I mentioned above, creating a fluid experience was at the top of my priorities while building this control.  To recreate the smooth scroll effect shown in the video we need to add some place holder storyboards that we can manipulate in code to simulate the inertia and snapping.  Using the easing functions built into Silverlight helps create a very pleasant interaction.    3.  Handle the Manipulation Events With Silverlight 3 we have some new touch event handlers.  The new Manipulation events makes handling the interactivity pretty straight forward.  There are two event handlers that need to be hooked up to enable the dragging and motion effects: the ManipulationDelta event :  (the most relevant code is highlighted in pink) Here we are doing some simple math with the Manipulation Deltas and setting the TO values of the animations appropriately. Modifying the storyboards dynamically in code helps to create a natural feel.something that cant easily be done with storyboards alone.   And secondly, the ManipulationCompleted event:  Here we take the Final Velocities from the Manipulation Completed Event and apply them to the Storyboards to create the snapping and scrolling effects.  Most of this code is determining what the next position of the viewport will be.  The interesting part (shown in pink) is determining the duration of the animation based on the calculated velocity of the flick gesture.  By using velocity as a variable in determining the duration of the animation we can produce a slow animation for a soft flick and a fast animation for a strong flick. Challenges to the Reader There are a couple of things I didnt have time to implement into this control.  And I would love to see other WPF/Silverlight approaches.  1.  A good mechanism for deciphering when the user is manipulating the content within the panorama control and the panorama itself.   In other words, being able to accurately determine what is a flick and what is click. 2.  Dynamically Sizing the panorama control based on the width of its content.  Right now each control panel is 400px, ideally the Panel items would be measured and then panorama control would update its size accordingly.  3.  Background and content wrapping.  The WP7 UX guidelines specify that the content and background should wrap at the end of the list.  In my code I restrict the drag at the ends of the list (like the iPhone).  It would be interesting to see how this would effect the scroll experience.     Well, Its been fun building this control and if you use it Id love to know what you think.  You can download the Source HERE or from the Expression Gallery  Erik Klimczak  | [email protected] | twitter.com/eklimczDid you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• CodePlex Daily Summary for Sunday, April 04, 2010

  CodePlex Daily Summary for Sunday, April 04, 2010New ProjectsAcervo 2 - Gerenciador de coleções: Acervo 2 is a web application developed in ASP.NET 3.5 with Entity Framework, Coolite UI web controls and MySQL database that helps to catalog and ...AssemblyInfo Editor: AssemblyInfo Editor is a small Visual Studio 2010 extension I developed for my personal use mainly for automatically incrementing AssemblyVersion a...CommLine: It's a Command Line Interpreter. At the moment, it's a beta version, so I wait for developers that wanna help meFlowgraph Viewer: The flowgraph viewer enables users to view, build and share flowgraphs for the Crysis-franchise. It's built on Silverlight4, using MEF and Mvvmlight.Hash Calculator: WPF Windows 7 program to compute SHA1 & MD5 hash functions.MediaRSS library for .NET: This is a small set of libraries that allow you to create, read, and write MediaRSS files. By leveraging the syndication model object in .NET this...MEF Visualizer Tool: Helps to see what is going on inside the CompositionContainerone framework for developing asp.net project more elegent、flexible、and testable: if you are familiar with jsf、cdi、scoped javabean and work under asp.net, you may want to support aop and max flexibility and testability , all of ...Picasa Manager: A Silverlight Out Of Browser Application that Helps you manage your PicasaWeb albums in the easyest way possible.SharePhone: Windows Phone 7 library for connecting to SharePoint 2007/2010. Lets you work with SPWeb, SPList, reading/writing strong typed list items, user ...Silverlight Resource Extension: Silverlight Resource Extension. Extension silverlight project for use ResX resources and localize satellite dll.Silverlight Streamgraph: Streamgraph component for SilverlightTFTP Server: Managed TFTP server implementation, written in C#. Supports: - IPv4 and IPv6 - correct retry behavior. - TFTP options: block size, transfer size, a...Virtual UserGroup Video Helpers: This is a project that holds all the tools used by the C4MVC Virtual Usergroup. Tools written in C# and Powershell to automate, Live Meeting, Expr...xBlog: xBlog is a project to build a simple and extensible Blog Engine based on xml and linqXmlCodeEditor: XmlCodeEditor is a Silverlight 4 control based on RichTextControl that creates coloring and intellisense similar to the one in Visual Studio for ed...Zinc Launcher: Zinc Launcher is a simple Windows Media Center plugin that launches Zinc and attempts to manage the windows as seamlessly as possible. In addition ...New ReleasesAcervo 2 - Gerenciador de coleções: Acervo 2 - v1.0: Arquivos para implantação do sistema Acervo2 Aplicação web Web service Smart ClientAssemblyInfo Editor: Beta 1: Initial release of Assembly Info Editor. At this point, it is feature-complete and is relatively stable. There are undoubtedly some bugs to work o...Box2D.XNA: Box2D.XNA r70 Source Code and Solution: This version is synced to changeset 44697. This represents our official port of the C Box2D up to r70 on the Google Code project. With this versi...Boxee Launcher: Boxee Launcher Release 1.0.1.2: Will now stop Media Center playback before launching BoxeeBoxee Launcher: Boxee Launcher Release 1.0.1.3: Added a background window that attempts to display over the desktop and taskbar, and below Boxee and Media Center so that the desktop and taskbar a...CommLine: Beta Version 0.1: First Beta Of the AppCommLine: Source v0.1 Beta: Source Code C of 0.1 beta versionEncrypted Notes: Encrypted Notes 1.6.2: This is the latest version of Encrypted Notes (1.6.2), with general changes and improved randomness for the key generator. It has an installer that...Hash Calculator: HashCalculator: HashCalculator 1.0Hash Calculator: HashCalculator Source code: HashCalculator 1.0Hulu Launcher: Hulu Launcher 1.0.1.3: Added a background window that attempts to display over the desktop and taskbar, and below Hulu and Media Center so that the desktop and taskbar ar...Hulu Launcher: Hulu Launcher Release 1.0.1.2: Hulu Launcher will now stop playback in Media Center before launching Hulu Desktop.Innovative Games: 4.3 - Sprite Effects: Source code download for chapter 4.3 - "Sprite Effects"MediaRSS library for .NET: 0.1: Alpha release. Majority of MediaRSS spec is supported. A small set of unit test / sample code are included. A lightly tested CustomFormatter object...MEF Visualizer Tool: MEF Visualizer Tool 0.1: Help to see what going on in side CompositionContainer Container = new CompositionContainer( new AggregateCatalog( ...Ncqrs Framework - A CQRS framework for .NET: Ncqrs with sample application: This is the first release of the Ncqrs Framework. It contains the Ncqrs source code and a runnable sample application. All the code in this release...Rubik Cube's 3D Silverlight 3.0 Animated Solution: Rubik Cube 3D with Animated Solution: This project is a realization of Silverlight 3.0 Rubik Cube 3D with Animated Solution. The Solution is available for 3x3x3 cube, other features are...Scrabler: scrabler release 0.6.2.5: fixed a bug that werent executed some scriptsSharePhone: SharePhone: Initial release with basic functionality: Open SharePoint webs and subwebs Retrieve lists on SPWeb objects Read metadata/properties on lists ...SharePhone: SharePhone v.1.0.1: Fixed a bug that prevented saving list items to SharePointSharePoint Labs: SPLab4001A-FRA-Level100: SPLab4001A-FRA-Level100 This SharePoint Lab will teach you the first best practice you should apply when writing code with the SharePoint API. Lab ...Silverlight Resource Extension: ResourceExtension (alpha): Alpha version is not stable. Only for review.Silverlight Streamgraph: Port from processing.org: A port from the processing.org streamgraph. Code-heavy with very little XAML involved at this point.Theocratic Ministry School System: TMSS - Ver 1.1.1: What’s New! Added Menu Options 2010 Schedule Access 2007 Runtime There are still many uncompleted items so this is still a conceptual release....Theocratic Ministry School System: TMSS - Ver 1.1.2: Fixed the Schedule Import. Need needs to be tested. Click import button and make sure you can get the 2010 Schedule from the internet.thinktecture Starter STS (Community Edition): StarterSTS v1.0 RTW: Version 1.0 RTWTribe.Cache: Tribe.Cache Alpha - 0.2.0.0: Tribe.Cache Alpha - 0.2.0.0 - Now has sliding and absolute expiration on cache entries. Functional Alpha Release - But do not use in productionTwitterVB - A .NET Twitter Library: TwitterVB-2.3.1: This is mostly a minor release that adds br.st URL shortening to the menu (API key from http://br.st required)Virtu: Virtu 0.8.1: Source Requirements.NET Framework 3.5 with Service Pack 1 Visual Studio 2008 with Service Pack 1, or Visual C# 2008 Express Edition with Service Pa...Visual Studio DSite: Advanced C++ Calculator: An advanced visual c 2008 calculator that can do all your basic operations, plus some advanced mathematical functions. Source Code Only.xnaWebcam: xnaWebcam 0.3: xnaWebcam 0.3 Version 0.3: -ResolutionSet: 400x300 (Default), 800x600, 1024x720 -Settings Window got Icon -Settings Window Changes -DevConsole.cs ...Most Popular ProjectsRawrWBFS ManagerMicrosoft SQL Server Product Samples: DatabaseASP.NET Ajax LibrarySilverlight ToolkitAJAX Control ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesDotNetNuke® Community EditionMost Active ProjectsGraffiti CMSnopCommerce. Open Source online shop e-commerce solution.RawrFacebook Developer ToolkitjQuery Library for SharePoint Web ServicesLINQ to TwitterBlogEngine.NETN2 CMSBase Class LibrariesFarseer Physics Engine

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• ComboBox Control using silverlight

  - by Aamir Hasan

  DropDown.zip (135.33 kb) LiveDemo Introduction In this article i am  going to explore some of the features of the ComboBox.ComboBox makes the collection visible and allows users to pick an item from the collection.After its first initialization, no matter if you bind a new datasource with fewer or more elements, the dropdown persists its original height.One workaround is the following:1. store the Properties from the original ComboBox2. delete the ComboBox removing it from its container3. create a new ComboBox and place it in the container4. recover the stores Properties5. bind the new DataSource to the newly created combobox Creating Silverlight ProjectCreate a new Silverlight 3 Project in VS 2008. Name it as ComboBoxtSample. Simple Data BindingAdd System.Windows.Control.Data reference to the Silverlight project. Silverlight UserControl Add a new page to display Bus data using DataGrid. Following shows Bus column XAML snippet:The ComboBox element represents a ComboBox control in XAML.  <ComboBox></ComboBox>ComboBox XAML        <StackPanel Orientation="Vertical">            <ComboBox Width="120" Height="30" x:Name="DaysDropDownList" DisplayMemberPath="Name">                <!--<ComboBox.ItemTemplate>                    <DataTemplate>                        <StackPanel Orientation="Horizontal">                            <TextBlock Text="{Binding Path=Name}" FontWeight="Bold"></TextBlock>                            <TextBlock Text=", "></TextBlock>                            <TextBlock Text="{Binding Path=ID}"></TextBlock>                        </StackPanel>                    </DataTemplate>                </ComboBox.ItemTemplate>-->            </ComboBox>        </StackPanel>   The following code below is an example implementation Combobox control support data binding     1 By setting the DisplayMemberPath property you can specify which data item in your data you want displayed in the ComboBox.    2 Setting the SelectedIndex allows you to specify which item in the ComboBox you want selected. Business Object public class Bus { public string Name { get; set; } public float Price { get; set; } }   Data Binding private List populatedlistBus() { listBus = new List(); listBus.Add(new Bus() {Name = "Bus 1", Price = 55f }); listBus.Add(new Bus() { Name = "Bus 2", Price = 55.7f }); listBus.Add(new Bus() { Name = "Bus 3", Price = 2f }); listBus.Add(new Bus() { Name = "Bus 4", Price = 6f }); listBus.Add(new Bus() { Name = "Bus 5", Price = 9F }); listBus.Add(new Bus() { Name = "Bus 6", Price = 10.1f }); return listBus; }   The following line of code sets the ItemsSource property of a ComboBox. DaysDropDownList.ItemsSource = populatedlistBus(); Output I hope you enjoyed this simple Silverlight example Conclusion In this article, we saw how data binding works in ComboBox.You learnt how to work with the ComboBox control in Silverlight.

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• Tweaking a few URL validation settings on ASP.NET v4.0

  - by Carlyle Dacosta

  ASP.NET has a few default settings for URLs out of the box. These can be configured quite easily in the web.config file within the  <system.web>/<httpRuntime> configuration section. Some of these are: <httpRuntime maxUrlLength=”<number here>” This number should be an integer value (defaults to 260 characters). The value must be greater than or equal to zero, though obviously small values will lead to an un-useable website. This attribute gates the length of the Url without query string. <httpRuntime maxQueryStringLength=”<number here>”. This number should be an integer value (defaults to 2048 characters). The value must be greater than or equal to zero, though obviously small values will lead to an un-useable website. <httpRuntime requestPathInvalidCharacters=”List of characters you need included in ASP.NETs validation checks” /> By default the characters are “<,>,*,%,&,:,\,?”. However once can easily change this by setting by modifying web.config. Remember, these characters can be specified in a variety of formats. For example, I want the character ‘!’ to be included in ASP.NETs URL validation logic. So I set the following: <httpRuntime requestPathInvalidCharacters=”<,>,*,%,&,:,\,?,!”. A character could also be specified in its xml encoded form. ‘&lt;;’ would mean the ‘<’ sign). I could specify the ‘!’ in its xml encoded unicode format such as requestPathInvalidCharacters=”<,>,*,%,&,:,\,?,$#x0021;” or I could specify it in its unicode encoded form or in the “<,>,*,%,&,:,\,?,%u0021” format. The following settings can be applied at Root Web.Config level, App Web.config level, Folder level or within a location tag: <location path="some path here"> <system.web> <httpRuntime maxUrlLength="" maxQueryStringLength="" requestPathInvalidChars="" /> .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; } If any of the above settings fail request validation, an Http 400 “Bad Request” HttpException is thrown. These can be easily handled on the Application_Error handler on Global.asax.   Also, a new attribute in <httpRuntime /> called “relaxedUrlToFileSystemMapping” has been added with a default of false. <httpRuntime … relaxedUrlToFileSystemMapping="true|false" /> When the relaxedUrlToFileSystemMapping attribute is set to false inbound Urls still need to be valid NTFS file paths. For example Urls (sans query string) need to be less than 260 characters; no path segment within a Url can use old-style DOS device names (LPT1, COM1, etc…); Urls must be valid Windows file paths. A url like “http://digg.com/http://cnn.com” should work with this attribute set to true (of course a few characters will need to be unblocked by removing them from requestPathInvalidCharacters="" above). Managed configuration for non-NTFS-compliant Urls is determined from the first valid configuration path found when walking up the path segments of the Url. For example, if the request Url is "/foo/bar/baz/<blah>data</blah>", and there is a web.config in the "/foo/bar" directory, then the managed configuration for the request comes from merging the configuration hierarchy to include the web.config from "/foo/bar". The value of the public property HttpRequest.PhysicalPath is set to [physical file path of the application root] + "REQUEST_URL_IS_NOT_A_VALID_FILESYSTEM_PATH". For example, given a request Url like "/foo/bar/baz/<blah>data</blah>", where the application root is "/foo/bar" and the physical file path for that root is "c:\inetpub\wwwroot\foo\bar", then PhysicalPath would be "c:\inetpub\wwwroot\foo\bar\ REQUEST_URL_IS_NOT_A_VALID_FILESYSTEM_PATH".

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• Parallelism in .NET – Part 8, PLINQ’s ForAll Method

  - by Reed

  Parallel LINQ extends LINQ to Objects, and is typically very similar.  However, as I previously discussed, there are some differences.  Although the standard way to handle simple Data Parellelism is via Parallel.ForEach, it’s possible to do the same thing via PLINQ. PLINQ adds a new method unavailable in standard LINQ which provides new functionality… LINQ is designed to provide a much simpler way of handling querying, including filtering, ordering, grouping, and many other benefits.  Reading the description in LINQ to Objects on MSDN, it becomes clear that the thinking behind LINQ deals with retrieval of data.  LINQ works by adding a functional programming style on top of .NET, allowing us to express filters in terms of predicate functions, for example. PLINQ is, generally, very similar.  Typically, when using PLINQ, we write declarative statements to filter a dataset or perform an aggregation.  However, PLINQ adds one new method, which provides a very different purpose: ForAll. The ForAll method is defined on ParallelEnumerable, and will work upon any ParallelQuery<T>.  Unlike the sequence operators in LINQ and PLINQ, ForAll is intended to cause side effects.  It does not filter a collection, but rather invokes an action on each element of the collection. At first glance, this seems like a bad idea.  For example, Eric Lippert clearly explained two philosophical objections to providing an IEnumerable<T>.ForEach extension method, one of which still applies when parallelized.  The sole purpose of this method is to cause side effects, and as such, I agree that the ForAll method “violates the functional programming principles that all the other sequence operators are based upon”, in exactly the same manner an IEnumerable<T>.ForEach extension method would violate these principles.  Eric Lippert’s second reason for disliking a ForEach extension method does not necessarily apply to ForAll – replacing ForAll with a call to Parallel.ForEach has the same closure semantics, so there is no loss there. Although ForAll may have philosophical issues, there is a pragmatic reason to include this method.  Without ForAll, we would take a fairly serious performance hit in many situations.  Often, we need to perform some filtering or grouping, then perform an action using the results of our filter.  Using a standard foreach statement to perform our action would avoid this philosophical issue: // Filter our collection var filteredItems = collection.AsParallel().Where( i => i.SomePredicate() ); // Now perform an action foreach (var item in filteredItems) { // These will now run serially item.DoSomething(); } .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; } This would cause a loss in performance, since we lose any parallelism in place, and cause all of our actions to be run serially. We could easily use a Parallel.ForEach instead, which adds parallelism to the actions: // Filter our collection var filteredItems = collection.AsParallel().Where( i => i.SomePredicate() ); // Now perform an action once the filter completes Parallel.ForEach(filteredItems, item => { // These will now run in parallel item.DoSomething(); }); This is a noticeable improvement, since both our filtering and our actions run parallelized.  However, there is still a large bottleneck in place here.  The problem lies with my comment “perform an action once the filter completes”.  Here, we’re parallelizing the filter, then collecting all of the results, blocking until the filter completes.  Once the filtering of every element is completed, we then repartition the results of the filter, reschedule into multiple threads, and perform the action on each element.  By moving this into two separate statements, we potentially double our parallelization overhead, since we’re forcing the work to be partitioned and scheduled twice as many times. This is where the pragmatism comes into play.  By violating our functional principles, we gain the ability to avoid the overhead and cost of rescheduling the work: // Perform an action on the results of our filter collection .AsParallel() .Where( i => i.SomePredicate() ) .ForAll( i => i.DoSomething() ); The ability to avoid the scheduling overhead is a compelling reason to use ForAll.  This really goes back to one of the key points I discussed in data parallelism: Partition your problem in a way to place the most work possible into each task.  Here, this means leaving the statement attached to the expression, even though it causes side effects and is not standard usage for LINQ. This leads to my one guideline for using ForAll: The ForAll extension method should only be used to process the results of a parallel query, as returned by a PLINQ expression. Any other usage scenario should use Parallel.ForEach, instead.

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• Windows Phone 7 development: first impressions

  - by DigiMortal

  After hard week in work I got some free time to play with Windows Phone 7 CTP developer tools. Although my first test application is still unfinished I think it is good moment to share my first experiences to you. In this posting I will give you quick overview of Windows Phone 7 developer tools from developer perspective. If you are familiar with Visual Studio 2010 then you will feel comfortable because Windows Phone 7 CTP developer tools base on Visual Studio 2010 Express. Project templates There are five project templates available. Three of them are based on Silverlight and two on XNA Game Studio: Windows Phone Application (Silverlight) Windows Phone List Application (Silverlight) Windows Phone Class Library (Silverlight) Windows Phone Game (XNA Game Studio) Windows Phone Game Library (XNA Game Studio) Currently I am writing to test applications. One of them is based on Windows Phone Application and the other on Windows Phone List Application project template. After creating these projects you see the following views in Visual Studio. Windows Phone Application. Click on image to enlarge. Windows Phone List Application. Click on image to enlarge.  I suggest you to use some of these templates to get started more easily. Windows Phone 7 emulator You can run your Windows Phone 7 applications on Windows Phone 7 emulator that comes with developer tools CTP. If you run your application then emulator is started automatically and you can try out how your application works in phone-like emulator. You can see screenshot of emulator on right. Currently there is opened Windows Phone List Application as it is created by default. Click on image to enlarge it. Emulator is a little bit slow and uncomfortable but it works pretty well. This far I have caused only couple of crashes during my experiments. In these cases emulator works but Visual Studio gets stuck because it cannot communicate with emulator. One important note. Emulator is based on virtual machine although you can see only phone screen and options toolbar. If you want to run emulator you must close all virtual machines running on your machine and run Visual Studio 2010 as administrator. Once you run emulator you can keep it open because you can stop your application in Visual Studio, modify, compile and re-deploy it without restarting emulator. Designing user interfaces You can design user interface of your application in Visual Studio. When you open XAML-files it is displayed in window with two panels. Left panel shows you device screen and works as visual design environment while right panel shows you XAML mark-up and let’s you modify XML if you need it. As it is one of my very first Silverlight applications I felt more comfortable with XAML editor because property names in property boxes of visual designer confused me a little bit. Designer panel is not very good because it is visually hard to follow. It has black background that makes dark borders of controls very hard to see. If you have monitor with very high contrast then it is may be not a real problem. I have usual monitor and I have problem. :) Putting controls on design surface, dragging and resizing them is also pretty painful. Some controls are drawn correctly but for some controls you have to set width and height in XML so they can be resized. After some practicing it is not so annoying anymore. On the right you can see toolbox with some controllers. This is all you get out of the box. But it is sufficient to get started. After getting some experiences you can create your own controls or use existing ones from other vendors or developers. If it is your first time to do stuff with Silverlight then keep Google open – you need it hard. After getting over the first shock you get the point very quickly and start developing at normal speed. :) Writing source code Writing source code is the most familiar part of this action. Good old Visual Studio code editor with all nice features it has. But here you get also some surprises: The anatomy of Silverlight controls is a little bit different than the one of user controls in web and forms projects. Windows Phone 7 doesn’t run on full version of Windows (I bet it is some version of Windows CE or something like this) then there is less system classes you can use. Some familiar classes have less methods that in full version of .NET Framework and in these cases you have to write all the code by yourself or find libraries or source code from somewhere. These problems are really not so much problems than limitations and you get easily over them. Conclusion Windows Phone 7 CTP developer tools help you do a lot of things on Windows Phone 7. Although I expected better performance from tools I think that current performance is not a problem. This far my first test project is going very well and Google has answer for almost every question. Windows Phone 7 is mobile device and therefore it has less hardware resources than desktop computers. This is why toolset is so limited. The more you need memory the more slower is device and as you may guess it needs the more battery. If you are writing apps for mobile devices then make your best to get your application use as few resources as possible and act as fast as possible.

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• Parallelism in .NET – Part 17, Think Continuations, not Callbacks

  - by Reed

  In traditional asynchronous programming, we’d often use a callback to handle notification of a background task’s completion.  The Task class in the Task Parallel Library introduces a cleaner alternative to the traditional callback: continuation tasks. Asynchronous programming methods typically required callback functions.  For example, MSDN’s Asynchronous Delegates Programming Sample shows a class that factorizes a number.  The original method in the example has the following signature: public static bool Factorize(int number, ref int primefactor1, ref int primefactor2) { //... .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; } However, calling this is quite “tricky”, even if we modernize the sample to use lambda expressions via C# 3.0.  Normally, we could call this method like so: int primeFactor1 = 0; int primeFactor2 = 0; bool answer = Factorize(10298312, ref primeFactor1, ref primeFactor2); Console.WriteLine("{0}/{1} [Succeeded {2}]", primeFactor1, primeFactor2, answer); If we want to make this operation run in the background, and report to the console via a callback, things get tricker.  First, we need a delegate definition: public delegate bool AsyncFactorCaller( int number, ref int primefactor1, ref int primefactor2); Then we need to use BeginInvoke to run this method asynchronously: int primeFactor1 = 0; int primeFactor2 = 0; AsyncFactorCaller caller = new AsyncFactorCaller(Factorize); caller.BeginInvoke(10298312, ref primeFactor1, ref primeFactor2, result => { int factor1 = 0; int factor2 = 0; bool answer = caller.EndInvoke(ref factor1, ref factor2, result); Console.WriteLine("{0}/{1} [Succeeded {2}]", factor1, factor2, answer); }, null); This works, but is quite difficult to understand from a conceptual standpoint.  To combat this, the framework added the Event-based Asynchronous Pattern, but it isn’t much easier to understand or author. Using .NET 4’s new Task<T> class and a continuation, we can dramatically simplify the implementation of the above code, as well as make it much more understandable.  We do this via the Task.ContinueWith method.  This method will schedule a new Task upon completion of the original task, and provide the original Task (including its Result if it’s a Task<T>) as an argument.  Using Task, we can eliminate the delegate, and rewrite this code like so: var background = Task.Factory.StartNew( () => { int primeFactor1 = 0; int primeFactor2 = 0; bool result = Factorize(10298312, ref primeFactor1, ref primeFactor2); return new { Result = result, Factor1 = primeFactor1, Factor2 = primeFactor2 }; }); background.ContinueWith(task => Console.WriteLine("{0}/{1} [Succeeded {2}]", task.Result.Factor1, task.Result.Factor2, task.Result.Result)); This is much simpler to understand, in my opinion.  Here, we’re explicitly asking to start a new task, then continue the task with a resulting task.  In our case, our method used ref parameters (this was from the MSDN Sample), so there is a little bit of extra boiler plate involved, but the code is at least easy to understand. That being said, this isn’t dramatically shorter when compared with our C# 3 port of the MSDN code above.  However, if we were to extend our requirements a bit, we can start to see more advantages to the Task based approach.  For example, supposed we need to report the results in a user interface control instead of reporting it to the Console.  This would be a common operation, but now, we have to think about marshaling our calls back to the user interface.  This is probably going to require calling Control.Invoke or Dispatcher.Invoke within our callback, forcing us to specify a delegate within the delegate.  The maintainability and ease of understanding drops.  However, just as a standard Task can be created with a TaskScheduler that uses the UI synchronization context, so too can we continue a task with a specific context.  There are Task.ContinueWith method overloads which allow you to provide a TaskScheduler.  This means you can schedule the continuation to run on the UI thread, by simply doing: Task.Factory.StartNew( () => { int primeFactor1 = 0; int primeFactor2 = 0; bool result = Factorize(10298312, ref primeFactor1, ref primeFactor2); return new { Result = result, Factor1 = primeFactor1, Factor2 = primeFactor2 }; }).ContinueWith(task => textBox1.Text = string.Format("{0}/{1} [Succeeded {2}]", task.Result.Factor1, task.Result.Factor2, task.Result.Result), TaskScheduler.FromCurrentSynchronizationContext()); This is far more understandable than the alternative.  By using Task.ContinueWith in conjunction with TaskScheduler.FromCurrentSynchronizationContext(), we get a simple way to push any work onto a background thread, and update the user interface on the proper UI thread.  This technique works with Windows Presentation Foundation as well as Windows Forms, with no change in methodology.

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• Using the HTML5 &lt;input type=&quot;file&quot; multiple=&quot;multiple&quot;&gt; Tag in ASP.NET

  - by Rick Strahl

  Per HTML5 spec the <input type="file" /> tag allows for multiple files to be picked from a single File upload button. This is actually a very subtle change that's very useful as it makes it much easier to send multiple files to the server without using complex uploader controls. Please understand though, that even though you can send multiple files using the <input type="file" /> tag, the process of how those files are sent hasn't really changed - there's still no progress information or other hooks that allow you to automatically make for a nicer upload experience without additional libraries or code. For that you will still need some sort of library (I'll post an example in my next blog post using plUpload). All the new features allow for is to make it easier to select multiple images from disk in one operation. Where you might have required many file upload controls before to upload several files, one File control can potentially do the job. How it works To create a file input box that allows with multiple file support you can simply do:<form method="post" enctype="multipart/form-data"> <label>Upload Images:</label> <input type="file" multiple="multiple" name="File1" id="File1" accept="image/*" /> <hr /> <input type="submit" id="btnUpload" value="Upload Images" /> </form> Now when the file open dialog pops up - depending on the browser and whether the browser supports it - you can pick multiple files. Here I'm using Firefox using the thumbnail preview I can easily pick images to upload on a form: Note that I can select multiple images in the dialog all of which get stored in the file textbox. The UI for this can be different in some browsers. For example Chrome displays 3 files selected as text next to the Browse… button when I choose three rather than showing any files in the textbox. Most other browsers display the standard file input box and display the multiple filenames as a comma delimited list in the textbox. Note that you can also specify the accept attribute in the <input> tag, which specifies a mime-type to specify what type of content to allow.Here I'm only allowing images (image/*) and the browser complies by just showing me image files to display. Likewise I could use text/* for all text formats registered on the machine or text/xml to only show XML files (which would include xml,xst,xsd etc.). Capturing Files on the Server with ASP.NET When you upload files to an ASP.NET server there are a couple of things to be aware of. When multiple files are uploaded from a single file control, they are assigned the same name. In other words if I select 3 files to upload on the File1 control shown above I get three file form variables named File1. This means I can't easily retrieve files by their name:HttpPostedFileBase file = Request.Files["File1"]; because there will be multiple files for a given name. The above only selects the first file. Instead you can only reliably retrieve files by their index. Below is an example I use in app to capture a number of images uploaded and store them into a database using a business object and EF 4.2.for (int i = 0; i < Request.Files.Count; i++) { HttpPostedFileBase file = Request.Files[i]; if (file.ContentLength == 0) continue; if (file.ContentLength > App.Configuration.MaxImageUploadSize) { ErrorDisplay.ShowError("File " + file.FileName + " is too large. Max upload size is: " + App.Configuration.MaxImageUploadSize); return View("UploadClassic",model); } var image = new ClassifiedsBusiness.Image(); var ms = new MemoryStream(16498); file.InputStream.CopyTo(ms); image.Entered = DateTime.Now; image.EntryId = model.Entry.Id; image.ContentType = "image/jpeg"; image.ImageData = ms.ToArray(); ms.Seek(0, SeekOrigin.Begin); // resize image if necessary and turn into jpeg Bitmap bmp = Imaging.ResizeImage(ms.ToArray(), App.Configuration.MaxImageWidth, App.Configuration.MaxImageHeight); ms.Close(); ms = new MemoryStream(); bmp.Save(ms,ImageFormat.Jpeg); image.ImageData = ms.ToArray(); bmp.Dispose(); ms.Close(); model.Entry.Images.Add(image); } This works great and also allows you to capture input from multiple input controls if you are dealing with browsers that don't support multiple file selections in the file upload control. The important thing here is that I iterate over the files by index, rather than using a foreach loop over the Request.Files collection. The files collection returns key name strings, rather than the actual files (who thought that was good idea at Microsoft?), and so that isn't going to work since you end up getting multiple keys with the same name. Instead a plain for loop has to be used to loop over all files. Another Option in ASP.NET MVC If you're using ASP.NET MVC you can use the code above as well, but you have yet another option to capture multiple uploaded files by using a parameter for your post action method.public ActionResult Save(HttpPostedFileBase[] file1) { foreach (var file in file1) { if (file.ContentLength < 0) continue; // do something with the file }} Note that in order for this to work you have to specify each posted file variable individually in the parameter list. This works great if you have a single file upload to deal with. You can also pass this in addition to your main model to separate out a ViewModel and a set of uploaded files:public ActionResult Edit(EntryViewModel model,HttpPostedFileBase[] uploadedFile) You can also make the uploaded files part of the ViewModel itself - just make sure you use the appropriate naming for the variable name in the HTML document (since there's Html.FileFor() extension). Browser Support You knew this was coming, right? The feature is really nice, but unfortunately not supported universally yet. Once again Internet Explorer is the problem: No shipping version of Internet Explorer supports multiple file uploads. IE10 supposedly will, but even IE9 does not. All other major browsers - Chrome, Firefox, Safari and Opera - support multi-file uploads in their latest versions. So how can you handle this? If you need to provide multiple file uploads you can simply add multiple file selection boxes and let people either select multiple files with a single upload file box or use multiples. Alternately you can do some browser detection and if IE is used simply show the extra file upload boxes. It's not ideal, but either one of these approaches makes life easier for folks that use a decent browser and leaves you with a functional interface for those that don't. Here's a UI I recently built as an alternate uploader with multiple file upload buttons: I say this is my 'alternate' uploader - for my primary uploader I continue to use an add-in solution. Specifically I use plUpload and I'll discuss how that's implemented in my next post. Although I think that plUpload (and many of the other packaged JavaScript upload solutions) are a better choice especially for large uploads, for simple one file uploads input boxes work well enough. The advantage of this solution is that it's very easy to handle on the server side. Any of the JavaScript controls require special handling for uploads which I'll also discuss in my next post.© Rick Strahl, West Wind Technologies, 2005-2012Posted in HTML5  ASP.NET  MVC   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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