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  • SQL SERVER – History of SQL Server Database Encryption

    - by pinaldave
    I recently met Michael Coles and Rodeney Landrum the author of one of the kind book Expert SQL Server 2008 Encryption at SQLPASS in Seattle. During the conversation we ended up how Microsoft is evolving encryption technology. The same discussion lead to talking about history of encryption tools in SQL Server. Michale pointed me to page 18 of his book of encryption. He explicitly give me permission to re-produce relevant part of history from his book. Encryption in SQL Server 2000 Built-in cryptographic encryption functionality was nonexistent in SQL Server 2000 and prior versions. In order to get server-side encryption in SQL Server you had to resort to purchasing or creating your own SQL Server XPs. Creating your own cryptographic XPs could be a daunting task owing to the fact that XPs had to be compiled as native DLLs (using a language like C or C++) and the XP application programming interface (API) was poorly documented. In addition there were always concerns around creating wellbehaved XPs that “played nicely” with the SQL Server process. Encryption in SQL Server 2005 Prior to the release of SQL Server 2005 there was a flurry of regulatory activity in response to accounting scandals and attacks on repositories of confidential consumer data. Much of this regulation centered onthe need for protecting and controlling access to sensitive financial and consumer information. With the release of SQL Server 2005 Microsoft responded to the increasing demand for built-in encryption byproviding the necessary tools to encrypt data at the column level. This functionality prominently featured the following: Support for column-level encryption of data using symmetric keys or passphrases. Built-in access to a variety of symmetric and asymmetric encryption algorithms, including AES, DES, Triple DES, RC2, RC4, and RSA. Capability to create and manage symmetric keys. Key creation and management. Ability to generate asymmetric keys and self-signed certificates, or to install external asymmetric keys and certificates. Implementation of hierarchical model for encryption key management, similar to the ANSI X9.17 standard model. SQL functions to generate one-way hash codes and digital signatures, including SHA-1 and MD5 hashes. Additional SQL functions to encrypt and decrypt data. Extensions to the SQL language to support creation, use, and administration of encryption keys and certificates. SQL CLR extensions that provide access to .NET-based encryption functionality. Encryption in SQL Server 2008 Encryption demands have increased over the past few years. For instance, there has been a demand for the ability to store encryption keys “off-the-box,” physically separate from the database and the data it contains. Also there is a recognized requirement for legacy databases and applications to take advantage of encryption without changing the existing code base. To address these needs SQL Server 2008 adds the following features to its encryption arsenal: Transparent Data Encryption (TDE): Allows you to encrypt an entire database, including log files and the tempdb database, in such a way that it is transparent to client applications. Extensible Key Management (EKM): Allows you to store and manage your encryption keys on an external device known as a hardware security module (HSM). Cryptographic random number generation functionality. Additional cryptography-related catalog views and dynamic management views. SQL language extensions to support the new encryption functionality. The encryption book covers all the tools in its various chapter in one simple story. If you are interested how encryption evolved and reached to the stage where it is today, this book is must for everyone. You can read my earlier review of the book over here. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Book Review, SQLAuthority News, T SQL, Technology Tagged: Encryption, SQL Server Encryption, SQLPASS

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  • MySQL – Learning MySQL Online in 6 Hours – MySQL Fundamentals in 320 Minutes

    - by Pinal Dave
    MySQL is one of the most popular database language and I have been recently working with it a lot. Data have no barrier and every database have their own place. I have been working with MySQL for quite a while and just like SQL Server, I often find lots of people asking me if I have a tutorial which can teach them MySQL from the beginning. Here is the good news, I have written two different courses on MySQL Fundamentals, which is available online. The reason for writing two different courses was to keep the learning simple. Both of the courses are absolutely connected with other but designed if you watch either of the course independently you can watch them and learn without dependencies. However, if you ask me, I will suggest that you watch MySQL Fundamentals Part 1 course following with MySQL Fundamentals Part 2 course. Let us quickly explore outline of MySQL courses. MySQL Fundamental – 1 (157 minutes) MySQL is a popular choice of database for use in web applications, and is a central component of the widely used LAMP open source web application software stack. This course covers the fundamentals of MySQL, including how to install MySQL as well as written basic data retrieval and data modification queries. Introduction (duration 00:02:12) Installations and GUI Tools (duration 00:13:51) Fundamentals of RDBMS and Database Designs (duration 00:16:13) Introduction MYSQL Workbench (duration 00:31:51) Data Retrieval Techniques (duration 01:11:13) Data Modification Techniques (duration 00:20:41) Summary and Resources (duration 00:01:31) MySQL Fundamental – 2 (163 minutes) MySQL is a popular choice of database for use in web applications, and is a central component of the widely used LAMP open source web application software stack. In this course, which is part 2 of the Fundamentals of MySQL series, we explore more advanced topics such as stored procedures & user-defined functions, subqueries & joins, views and events & triggers. Introduction (duration 00:02:09) Joins, Unions and Subqueries (duration 01:03:56) MySQL Functions (duration 00:36:55) MySQL Views (duration 00:19:19) Stored Procedures and Stored Functions (duration 00:25:23) Triggers and Events (duration 00:13:41) Summary and Resources (duration 00:02:18) Note if you click on the link above and you do not see the play button to watch the course, you will have to login to the system and watch the course. I would like to throw a challenge to you – Can you watch both of the courses in a single day? If yes, once you are done watching the course on your Pluralsight Profile Page (here is my profile http://pluralsight.com/training/users/pinal-dave) you will get following badges. If you have already watched MySQL Fundamental Part 1, you can qualify by just watching MySQL Fundamental Part 2. Just send me the link to your profile and I will publish your name on this blog. For the first five people who send me email at Pinal at sqlauthority.com; I might have something cool as a giveaway as well. Watch the teaser of MySQL course. Reference: Pinal Dave (http://blog.sqlauthority.com)  Filed under: MySQL, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • West Palm Beach Developers&rsquo; Group June 2013 Meeting Recap &ndash; ASP.NET Web API and Web Sockets with Shervin Shakibi

    - by Sam Abraham
    Originally posted on: http://geekswithblogs.net/wildturtle/archive/2013/07/02/west-palm-beach-developersrsquo-group-june-2013-meeting-recap-ndash.aspxOur West Palm Beach Developers’ Group June 2013 meeting featured Shervin Shakibi, Microsoft Regional Director and Certified Trainer. Shervin spoke on the ASP.NET Web API and Web Sockets, two new features shipped along with ASP.NET MVC4. Talk was simply awesome and very interactive as Shervin answered many audience questions. Our event was sponsored by Steven Douglas Associates and hosted by PC Professor. Below are some photos of our event (Pardon my flash malfunction):   Shervin Presenting on the Web API A partial view of the standing-room only meeting.

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  • Lessons from a SAN Failure

    - by Bill Graziano
    At 1:10AM Sunday morning the main SAN at one of my clients suffered a “partial” failure.  Partial means that the SAN was still online and functioning but the LUNs attached to our two main SQL Servers “failed”.  Failed means that SQL Server wouldn’t start and the MDF and LDF files mostly showed a zero file size.  But they were online and responding and most other LUNs were available.  I’m not sure how SANs know to fail at 1AM on a Saturday night but they seem to.  From a personal standpoint this worked out poorly: I was out with friends and after more than a few drinks.  From a work standpoint this was about the best time to fail you could imagine.  Everything was running well before Monday morning.  But it was a long, long Sunday.  I started tipsy, got tired and ended up hung over later in the day. Note to self: Try not to go out drinking right before the SAN fails. This caught us at an interesting time.  We’re in the process of migrating to an entirely new set of servers so some things were partially moved.  This made it difficult to follow our procedures as cleanly as we’d like.  The benefit was that we had much better documentation of everything on the server.  I would encourage everyone to really think through the process of implementing your DR plan and document as much as possible.  Following a checklist is much easier than trying to remember at night under pressure in a hurry after a few drinks. I had a series of estimates on how long things would take.  They were accurate for any single server failure.  They weren’t accurate for a SAN failure that took two servers down.  This wasn’t bad but we should have communicated better. Don’t forget how many things are outside the database.  Logins, linked servers, DTS packages (yikes!), jobs, service broker, DTC (especially DTC), database triggers and any objects in the master database are all things you need backed up.  We’d done a decent job on this and didn’t find significant problems here.  That said this still took a lot of time.  There were many annoyances as a result of this.  Small settings like a login’s default database had a big impact on whether an application could run.  This is probably the single biggest area of concern when looking to recreate a server.  I’d encourage everyone to go through every single node of SSMS and look for user created objects or settings outside the database. Script out your logins with the proper SID and already encrypted passwords and keep it updated.  This makes life so much easier.  I used an approach based on KB246133 that worked well.  I’ll get my scripts posted over the next few days. The disaster can cause your DR process to fail in unexpected ways.  We have a job that scripts out all logins and role memberships and writes it to a file.  This runs on the DR server and pulls from the production server.  Upon opening the file I found that the contents were a “server not found” error.  Fortunately we had other copies and didn’t need to try and restore the master database.  This now runs on the production server and pushes the script to the DR site.  Soon we’ll get it pushed to our version control software. One of the biggest challenges is keeping your DR resources up to date.  Any server change (new linked server, new SQL Server Agent job, etc.) means that your DR plan (and scripts) is out of date.  It helps to automate the generation of these resources if possible. Take time now to test your database restore process.  We test ours quarterly.  If you have a large database I’d also encourage you to invest in a compressed backup solution.  Restoring backups was the single larger consumer of time during our recovery. And yes, there’s a database mirroring solution planned in our new architecture. I didn’t have much involvement in things outside SQL Server but this caused many, many things to change in our environment.  Many applications today aren’t just executables or web sites.  They are a combination of those plus network infrastructure, reports, network ports, IP addresses, DTS and SSIS packages, batch systems and many other things.  These all needed a little bit of attention to make sure they were functioning properly. Profiler turned out to be a handy tool.  I started a trace for failed logins and kept that running.  That let me fix a number of problems before people were able to report them.  I also ran traces to capture exceptions.  This helped identify problems with linked servers. Overall the thing that gave me the most problem was linked servers.  In order for a linked server to function properly you need to be pointed to the right server, have the proper login information, have the network routes available and have MSDTC configured properly.  We have a lot of linked servers and this created many failure points.  Some of the older linked servers used IP addresses and not DNS names.  This meant we had to go in and touch all those linked servers when the servers moved.

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  • POP Forums v9 Beta 1 for ASP.NET MVC 3 posted to CodePlex!

    - by Jeff
    As promised, I posted a beta build of my forum app for ASP.NET MVC 3. Get the new goodies here: http://popforums.codeplex.com/releases/view/58228 This is the first beta for the ASP.NET MVC 3 version of POP Forums. It is nearly feature complete, and ready for testing and feedback. For previous release notes, look here, here and here.Check out the live preview: http://preview.popforums.com/ForumsSetup instructions are on the home page of this project. The new hotness in the beta, or what has been done since the last preview: All views converted to use Razor E-mail subscription/notification of new posts New post indicators/mark read buttons Permalinks to posts Jump to newest post (from new post indicators) Recent topics Favorite topics Moderator functions for topics (pin/close/delete, plus move and rename) Search, ported from v8. Not a ton of optimization here, or new unit testing, but the old version worked pretty well User posts (topics the user posted in) Forgot password Vanity items (signatures and avatars) Hide vanity items per user preference Some minor data caching where appropriate A little bit of UI refinement Lots-o-bug fixes Lots-o-unit tests What's next? The plan between now and the next beta is as follows: Continue working through features/tasks, and fix bugs as they're reported Integrate the forum into a real, production site Refine the UI Refactor as much as possible... the code organization is not entirely logical in some places After the second beta, a release candidate will follow, with a real "final" release after that. Subsequent releases should come relatively frequently and without a lot of risk. The trick in building this thing has been that it mostly tossed the previous WebForms version, which was all full of crusties. The time table for this is a little harder to pin down, as day jobs and families will have their effect. Other notes Refactoring will be a priority. As the features of MVC have evolved, so have my desires to use it in a fashion that makes things clear and easy to follow. I don't even know if anyone will ever start mucking around in the code, but on the off chance they do, I'd like what they find to not suck. Other nice-to-haves are builds to target Windows Azure and SQL CE. A nice setup UI would be super too. I think the ASP.NET MVC world has gone long enough without a decent forum.The biggest challenge that I've found is making the forum something that can be dropped in any app. While it does rope its views into an area, areas are mostly just routing details. I haven't thought of a clever way yet to limit dependency injection, for example, to just the forum bits. I mean, everyone should be using Ninject, but how realistic is that? ;)How much time and effort should you spend on POP Forums in its current state? Change is inevitable, but at this point I'm reasonably committed to not changing the database schema. I really think it will stay as-is. All bets are off for the various interfaces throughout the app, but the data should generally resist change. It's not even that different from v8, which was one of the original goals because I didn't want to rewrite SQL or introduce a new ORM or whatever. My point is that if you wanted to build a site around this today, even though it's not entirely functional, I think it's low risk in terms of data loss. I can't vouch for whether or not you know what you're doing.I've been having some chats with people lately about quoting posts, and honestly there has to be something better and straight forward. That continues to be a holy grail of mine, and some day, I hope to find it.Enjoy... it's starting to feel more real every day!

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  • Introducing .NET 4.0 with Visual Studio 2010 by Alex Mackey - Book review

    - by Malisa L. Ncube
    Alex (http://simpleisbest.co.uk/) does a very good job in covering the new features of .NET 4.0 and Visual Studio 2010. His focus is on the developers that have experience in development using previous versions of Visual Studio, more specifically Visual Studio 2008.     The following are my views towards his book. 1. Scope / Coverage Even as the book is labeled as introduction, it is covers a broad spectrum of technologies, features and references that are focused into helping a developer quickly decide what to use in the new .NET framework. a. Content The content included covers as much as possible the new additions that are included in the new .NET version 4.0. He shows the Visual Studio 2010 new features and quickly shows how to extend it using Managed Extensibility Framework. Some of my favorites are parallel debugging enhancements. The author delves into JQuery, which Microsoft has decided to support. Some of the very interesting content is on the out-of-band releases including ASP.NET MVC, Windows Azure Silverlight 3 and WCF Data Services. b. What is not included? Windows Phone 7 Series. This was only talked about in the MIX10. The data may not have been available at the time of writing. Microsoft Pinpoint (Microsoft code name "Dallas") Windows Embedded development. c. Table of Contents Chapter 1: Introduction Chapter 2: Visual Studio IDE and MEF Chapter 3: Language and Dynamic Changes Chapter 4: CLR and BCL Changes Chapter 5: Parallelization and Threading Enhancements Chapter 6: Windows Workflow Foundation 4 Chapter 7: Windows Communication Foundation Chapter 8: Entity Framework Chapter 9: WCF Data Services Chapter 10: ASPNET Chapter 11: Microsoft AJAX Library Chapter 12: jQuery Chapter 13: ASPNET MVC Chapter 14: Silverlight Introduction Chapter 15: WPF 4.0 and Silverlight 3.0 Chapter 16: Windows Azure 2. Depth Avoids getting into depth on the topics presented, to present the new concepts in assumption of the developer’s existing knowledge. Code samples are on book and exist mostly as snippets and very easy to follow. There are no downloadable examples. 3. Complexity The book is written in a very simple way and easy to follow. There are no irrelevant intimidating details. So it’s a book that you can grab and never put down until you’ve finished reading the entire book. 4. References The author includes reference links to blogs, Wikis and a lot of online resources including the MSDN documentation, which is a very convenient strategy to avoid flooding the reader with details which may not be of interest to them. Most sites do not use url routing and that is really not nice. There are notes from interviews between the author and people behind the new technologies, in which they explain what some specific areas that need clarifications and what their future views are in relation to the features they are working on. 5. Target The author targets experts that want to make a transition from .NET 3.5 to 4.0. Some obvious 3.5 features have been purposely excluded from the text 6. Overrall It is evident that the author has made extensive research into the breadth of what MS is working on, in relation to .NET and Visual Studio and has also been watching the online community. What I would like to see in the next edition are some details on OData protocol, Expression Blend 4 and Embedded development and Windows Phone development. I should say I’m one of the beneficiaries of this book. Excellent work Alex.   Technorati Tags: .NET,Book-Review,Visual Studio

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  • What Functional features are worth a little OOP confusion for the benefits they bring?

    - by bonomo
    After learning functional programming in Haskell and F#, the OOP paradigm seems ass-backwards with classes, interfaces, objects. Which aspects of FP can I bring to work that my co-workers can understand? Are any FP styles worth talking to my boss about retraining my team so that we can use them? Possible aspects of FP: Immutability Partial Application and Currying First Class Functions (function pointers / Functional Objects / Strategy Pattern) Lazy Evaluation (and Monads) Pure Functions (no side effects) Expressions (vs. Statements - each line of code produces a value instead of, or in addition to causing side effects) Recursion Pattern Matching Is it a free-for-all where we can do whatever the programming language supports to the limit that language supports it? Or is there a better guideline?

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  • OWB 11gR2 - Find and Search Metadata in Designer

    - by David Allan
    Here are some tools and techniques for finding objects, specifically in the design repository. There are ways of navigating and collating objects that are useful for day to day development and build-time usage - this includes features out of the box and utilities constructed on top. There are a variety of techniques to navigate and find objects in the repository, the first 3 are out of the box, the 4th is an expert utility. Navigating by the tree, grouping by project and module - ok if you are aware of the exact module/folder that objects reside in. The structure panel is a useful way of finding parts of an object, especially when large rather than using the canvas. In large scale projects it helps to have accelerators (either find or collections below). Advanced find to search by name - 11gR2 included a find capability specifically for large scale projects. There were improvements in both the tree search and the object editors (including highlighting in mapping for example). So you can now do regular expression based search and quickly navigate to objects within a repository. Collections - logically organize your objects into virtual folders by shortcutting the actual objects. This is useful for a range of things since all the OWB services operate on collections too (export/import, validation, deployment). See the post here for new collection functionality in 11gR2. Reports for searching by type, updated on, updated by etc. Useful for activities such as periodic incremental actions (deploy all mappings changed in the past week). The report style view is useful since I can quickly see who changed what and when. You can see all the audit details for objects within each objects property inspector, but its useful to just get all objects changed today or example, all objects changed since my last build etc. This utility combines both UI extensions via experts and the public views on the repository. In the figure to the right you see the contextual option 'Object Search' which invokes the utility, you can see I have quite a number of modules within my project. Figure out all the potential objects which have been changed is not simple. The utility is an expert which provides this kind of search capability. The utility provides a report of the objects in the design repository which satisfy some filter criteria. The type of criteria includes; objects updated in the last n days optionally filter the objects updated by user filter the user by project and by type (table/mappings etc.) The search dialog appears with these options, you can multi-select the object types, so for example you can select TABLE and MAPPING. Its also possible to search across projects if need be. If you have multiple users using the repository you can define the OWB user name in the 'Updated by' property to restrict the report to just that user also. Finally there is a search name that will be used for some of the options such as building a collection - this name is used for the collection to be built. In the example I have done, I've just searched my project for all process flows and mappings that users have updated in the last 7 days. The results of the query are returned in a table containing the object names, types, full path and audit details. The columns are sort-able, you can sort the results by name, type, path etc. One of the cool things here, is that you can then perform operations on these objects - such as edit them, export single selection or entire results to MDL, create a collection from the results (now you have a saved set of references in the repository, you could do deploy/export etc.), create a deployment script from the results...or even add in your own ideas! You see from this that you can do bulk operations on sets of objects based on search results. So for example selecting the 'Build Collection' option creates a collection with all of the objects from my search, you can subsequently deploy/generate/maintain this collection of objects. Under the hood of the expert if just basic OMB commands from the product and the use of the public views on the design repository. You can see how easy it is to build up macro-like capabilities that will help you do day-to-day as well as build like tasks on sets of objects.

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  • Popup Details for a Table Record

    - by shay.shmeltzer
    This one started as an OTN how-to question that seemed like something that should work automatically - turns out you need a couple of small tweaks to get it working. The idea is to have a table on a page showing multiple records, you can click any row in the table - and get a pop-up window that shows more data about that row. At first I thought I'll just need to drag the same view twice to the page - once as a table and then as a form in a pop-up. But then the Form didn't reflect the new row that got selected in the table - you'll always see the first row you selected. Adding a Partial Page Rendering between the table and the pop-up didn't do the trick either. Then I realized that the content delivery attribute of the pop-up was set to lazy, when I switched it to immediate - everything worked. Here is a little demo showing the whole development process: Note that the content delivery method attribute is also something you might want to check if you see your tables being refreshed too often when you scroll through records for example.

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  • Curiosity’s Self Portrait

    - by Jason Fitzpatrick
    One space enthusiast couldn’t wait for NASA to release an official on-Mars portrait of the rover Curiosity, so he took 55 partial self-portraits sent back by the rover and stitched them all together into the first complete on-planet photo we’ve seen of Curiosity. Courtesy of Stuart Atkinson, the photos are stitched together from images collected over the initial portion of Curiosity’s mission. Hit up the link below to check out the full size image. Curiosity [via Wired] 6 Start Menu Replacements for Windows 8 What Is the Purpose of the “Do Not Cover This Hole” Hole on Hard Drives? How To Log Into The Desktop, Add a Start Menu, and Disable Hot Corners in Windows 8

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  • Odd MVC 4 Beta Razor Designer Issue

    - by Rick Strahl
    This post is a small cry for help along with an explanation of a problem that is hard to describe on twitter or even a connect bug and written in hopes somebody has seen this before and any ideas on what might cause this. Lots of helpful people had comments on Twitter for me, but they all assumed that the code doesn't run, which is not the case - it's a designer issue. A few days ago I started getting some odd problems in my MVC 4 designer for an app I've been working on for the past 2 weeks. Basically the MVC 4 Razor designer keeps popping me errors, about the call signature to various Html Helper methods being incorrect. It also complains about the ViewBag object and not supporting dynamic requesting to load assemblies into the project. Here's what the designer errors look like: You can see the red error underlines under the ViewBag and an Html Helper I plopped in at the top to demonstrate the behavior. Basically any HtmlHelper I'm accessing is showing the same errors. Note that the code *runs just fine* - it's just the designer that is complaining with Errors. What's odd about this is that *I think* this started only a few days ago and nothing consequential that I can think of has happened to the project or overall installations. These errors aren't critical since the code runs but pretty annoying especially if you're building and have .csHtml files open in Visual Studio mixing these fake errors with real compiler errors. What I've checked Looking at the errors it indeed looks like certain references are missing. I can't make sense of the Html Helpers error, but certainly the ViewBag dynamic error looks like System.Core or Microsoft.CSharp assemblies are missing. Rest assured they are there and the code DOES run just fine at runtime. This is a designer issue only. I went ahead and checked the namespaces that MVC has access to in Razor which lives in the Views folder's web.config file: /Views/web.config For good measure I added <system.web.webPages.razor> <host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, <split for layout> Version=4.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" /> <pages pageBaseType="System.Web.Mvc.WebViewPage"> <namespaces> <add namespace="System.Web.Mvc" /> <add namespace="System.Web.Mvc.Ajax" /> <add namespace="System.Web.Mvc.Html" /> <add namespace="System.Web.Routing" /> <add namespace="System.Linq" /> <add namespace="System.Linq.Expressions" /> <add namespace="ClassifiedsBusiness" /> <add namespace="ClassifiedsWeb"/> <add namespace="Westwind.Utilities" /> <add namespace="Westwind.Web" /> <add namespace="Westwind.Web.Mvc" /> </namespaces> </pages> </system.web.webPages.razor> For good measure I added System.Linq and System.Linq.Expression on which some of the Html.xxxxFor() methods rely, but no luck. So, has anybody seen this before? Any ideas on what might be causing these issues only at design time rather, when the final compiled code runs just fine?© Rick Strahl, West Wind Technologies, 2005-2012Posted in Razor  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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  • sudo apt-get update error

    - by Kapil Anand
    I got the following error Reading package lists... Done W: GPG error: http://extras.ubuntu.com oneiric Release: Unknown error executing gpgv executing gpgv ---- W: GPG error: http://archive.ubuntu.com oneiric-updates Release: Unknown error executing gpgv Then after googling it i found and followed the following but that caused one error **sudo -i apt-get clean cd /var/lib/apt mv lists lists.old mkdir -p lists/partial apt-get clean apt-get update** while running i got the error " kapil@ubuntu:/var/lib/apt$ sudo mv lists lists.old mv: cannot move `lists' to `lists.old/lists': Directory not empty " so once again running the update command I got the same error again. Please help me what should i do?

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  • Enable Multi-Column Google Searches with a User Script

    - by Asian Angel
    Are you wanting to improve the search results view at Google and make better use of the webpage space? With a little user script magic you can make those search results look and fit better in your favorite browser. Note: This user script may conflict with the AutoPager extension if you have it installed in your favorite browser. Before Here is the standard single column view of search results at Google. Not too bad but the available space could certainly be better utilized. Note: For the purposes of our example we are using Google Chrome but this user script can be easily added to other browsers. After If you have never installed a user script in Chrome before it is just as simple as the regular extensions at the official Google website. Here you can see the details for the user script we are installing. Notice that you can view the source code if desired. To add the user script to Chrome click on “Install”. Once you start the install process you will see an intermediary message asking if you wish to continue in the lower left corner of your browser. Click “Continue” to move to the next step in the install process. From this point on the install process is practically identical to the official extensions. You can see the final confirmation window here…click “Install” to finish adding the user script to Chrome. As with regular extensions you will see a post-install message in the upper right corner. So, what does a user script look like in the “Extensions Page”? You can see the user script entry here…outside of an icon it looks rather identical to a normal extension. After refreshing the search page shown above we now have two columns of search results (default setting). This looks much much better than a single column view and there is little to no page scrolling required now. To switch to a three column view simply use the keyboard shortcut “Alt + 3”. To return to a single column view use “Alt + 1” and for the default two column view use “Alt + 2”. Three keyboard shortcuts for three different views…definitely a good thing. Note: On our test system we needed to use the number keys at the top of our keyboard to switch views…this is most likely the result of unique settings on our test system. Conclusion If you are wanting a better viewing experience when conducting searches at Google then this user script will make a very nice addition to your favorite browser. For those using Firefox you can add user scripts with the Greasemonkey & Stylish extensions. Using Opera Browser? See our how-to for adding user scripts to Opera here. Links Install the Multi-Column View of Google Search Results User Script Similar Articles Productive Geek Tips Hide Flash Animations in Google ChromeEnable Google Search From Shortcut Key in KDE on (k)UbuntuSet Gmail as Default Mail Client in UbuntuSet Up User Scripts in Opera BrowserHow To Enable Favicons for Google Reader Subscriptions 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 DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Yes, it’s Patch Tuesday Generate Stunning Tag Clouds With Tagxedo Install, Remove and HIDE Fonts in Windows 7 Need Help with Your Home Network? Awesome Lyrics Finder for Winamp & Windows Media Player Download Videos from Hulu

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  • Html.RenderAction Failed when Validation Failed

    - by Shaun
    RenderAction method had been introduced when ASP.NET MVC 1.0 released in its MvcFuture assembly and then final announced along with the ASP.NET MVC 2.0. Similar as RenderPartial, the RenderAction can display some HTML markups which defined in a partial view in any parent views. But the RenderAction gives us the ability to populate the data from an action which may different from the action which populating the main view. For example, in Home/Index.aspx we can invoke the Html.RenderPartial(“MyPartialView”) but the data of MyPartialView must be populated by the Index action of the Home controller. If we need the MyPartialView to be shown in Product/Create.aspx we have to copy (or invoke) the relevant code from the Index action in Home controller to the Create action in the Product controller which is painful. But if we are using Html.RenderAction we can tell the ASP.NET MVC from which action/controller the data should be populated. in that way in the Home/Index.aspx and Product/Create.aspx views we just need to call Html.RenderAction(“CreateMyPartialView”, “MyPartialView”) so it will invoke the CreateMyPartialView action in MyPartialView controller regardless from which main view. But in my current project we found a bug when I implement a RenderAction method in the master page to show something that need to connect to the backend data center when the validation logic was failed on some pages. I created a sample application below.   Demo application I created an ASP.NET MVC 2 application and here I need to display the current date and time on the master page. I created an action in the Home controller named TimeSlot and stored the current date into ViewDate. This method was marked as HttpGet as it just retrieves some data instead of changing anything. 1: [HttpGet] 2: public ActionResult TimeSlot() 3: { 4: ViewData["timeslot"] = DateTime.Now; 5: return View("TimeSlot"); 6: } Next, I created a partial view under the Shared folder to display the date and time string. 1: <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<dynamic>" %> 2:  3: <span>Now: <% 1: : ViewData["timeslot"].ToString() %></span> Then at the master page I used Html.RenderAction to display it in front of the logon link. 1: <div id="logindisplay"> 2: <% 1: Html.RenderAction("TimeSlot", "Home"); %> 3:  4: <% 1: Html.RenderPartial("LogOnUserControl"); %> 5: </div> It’s fairly simple and works well when I navigated to any pages. But when I moved to the logon page and click the LogOn button without input anything in username and password the validation failed and my website crashed with the beautiful yellow page. (I really like its color style and fonts…)   How ASP.NET MVC executes Html.RenderAction In this example all other pages were rendered successful which means the ASP.NET MVC found the TimeSolt action under the Home controller except this situation. The only different is that when I clicked the LogOn button the browser send an HttpPost request to the server. Is that the reason of this bug? I created another action in Home controller with the same action name but for HttpPost. 1: [HttpPost] 2: [ActionName("TimeSlot")] 3: public ActionResult TimeSlot(object dummy) 4: { 5: return TimeSlot(); 6: } Or, I can use the AcceptVerbsAttribute on the TimeSlot action to let it allow both HttpGet and HttpPost. 1: [AcceptVerbs("GET", "POST")] 2: public ActionResult TimeSlot() 3: { 4: ViewData["timeslot"] = DateTime.Now; 5: return View("TimeSlot"); 6: } And then repeat what I did before and this time it worked well. Why we need the action for HttpPost here as it’s just data retrieving? That is because of how ASP.NET MVC executes the RenderAction method. In the source code of ASP.NET MVC we can see when proforming the RenderAction ASP.NET MVC creates a RequestContext instance from the current RequestContext and created a ChildActionMvcHandler instance which inherits from MvcHandler class. Then the ASP.NET MVC processes the handler through the HttpContext.Server.Execute method. That means it performs the action as a stand-alone request asynchronously and flush the result into the  TextWriter which is being used to render the current page. Since when I clicked the LogOn the request was in HttpPost so when ASP.NET MVC processed the ChildActionMvcHandler it would find the action which allow the current request method, which is HttpPost. Then our TimeSlot method in HttpGet would not be matched.   Summary In this post I introduced a bug in my currently developing project regards the new Html.RenderAction method provided within ASP.NET MVC 2 when processing a HttpPost request. In ASP.NET MVC world the underlying Http information became more important than in ASP.NET WebForm world. We need to pay more attention on which kind of request it currently created and how ASP.NET MVC processes.   Hope this helps, Shaun   All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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  • ASP.NET 4 Website Fails to Start on Your TFS 2010 Server?

    - by jdanforth
    Getting a “Could not find permission set named ‘ASP.Net’” error on your TFS 2010 server? It may have to do with the fact you’re trying to run ASP.NET as a child site of a SharePoint Web Site. The problem is described in the “ASP.NET 4 braking changes” site:   This error occurs because the ASP.NET 4 code access security (CAS) infrastructure looks for a permission set named ASP.Net. However, the partial trust configuration file that is referenced by WSS_Minimal does not contain any permission sets with that name. Currently there is not a version of SharePoint available that is compatible with ASP.NET. As a result, you should not attempt to run an ASP.NET 4 Web site as a child site underneath SharePoint Web sites.   There is a workaround you could try by setting this in your web.config, if you know what you’re doing: <trust level="Full" originUrl="" />

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  • Technologies similar to Flash and Silverlight for Desktop apps

    - by M.A. Hanin
    Long story short: we use Flash as a partial GUI in our .NET desktop applications. Normally, this means that the Flash player control sits in some WinForm, playing a movie file. Changes in the real world are presented in the movie (e.g., a light-bulb turned on in the real world? a matching one will light up inside the Flash movie), and interaction with the instances in the movie will affect the real world (clicked the light-bulb? the light bulb in the real world will turn on). My question is: which technologies / products can offer me similar capabilities? Of course, I'm looking for something that can compete with Flash / Silverlight: animations, object-oriented scripting and design, powerful tools allowing the artists to design symbols conveniently, etc... static image objects won't cut it

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  • 'Important security update' for Firefox and flash plugin, but the update cannot be selected

    - by geoffrey
    [This question has been updated as I now have the same problem with Firefox in addition to flash plugin] The update manager (on Ubuntu 12.04, 64bit) shows an 'important security update' for flashplugin-installer:i386, firefox, and firefox-globalmenu. The update is unticked, and cannot be selected, and therefore cannot be updated (I can update other packages without problems). Actually the flashplugin-installer package does not appear to be installed on my computer (judging from the Software Centre). I can't remember how I installed flash, probably directly from the Adobe website. The updater asks me if I want to do a partial upgrade. When running sudo apt-get update && sudo apt-get upgrade from terminal, I get the following: The following packages have been kept back: firefox firefox-globalmenu flashplugin-installer:i386

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  • Name a Byobu session?

    - by Ashimema
    Is there a way to create identifiable Byobu sessions so that when I've got multiple sessions running, the byobu-select-session menu gives me a list of sessions I can recognize, as opposed to non-descript tmux port numbers? In an ideal world, it would be great to be able to both start a session giving it a name and to modify such a session to change a name if it's already running? Is this possible, how? Edit 1: Some further details: I'm using tmux as the backend and don't especially want to switch back to screen. I've now tried starting a session with byobu -S "Name" to no avail :-( Edit 2: Some discoveries: I've now discovered a partial answer in using tmux native commands: tmux rename-session <current-name> <new-name> renames an existing session and tmux new -s session_name creates a new names session. I'm surprised byobu -S "name" isn't liked to tmux new -s session_name for byobu with a tmux backend.

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  • Ubuntu Extras keyring error

    - by Pawan Neupane
    Recently I got lots of GPG errors and tried the following methods at various stages: sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 3E5C1192 sudo apt-get install -reinstall ubuntu-extras-keyring (For Ubuntu Extras only) gpg –keyserver keyserver.ubuntu.com –recv 3E5C1192 gpg –export –armor 3E5C1192 | sudo apt-key add - sudo apt-get update sudo aptitude -o Acquire::http::No-Cache=True -o Acquire::BrokenProxy=true update sudo -i apt-get clean cd /var/lib/apt mv lists lists.old mkdir -p lists/partial apt-get clean apt-get update I again got BADSIG error for extras.ubuntu.com today. So, I'm really at a loss what's causing this error to occur time and again. I really want to solve this problem once and for all.

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  • Creating shapes on the fly

    - by Bertrand Le Roy
    Most Orchard shapes get created from part drivers, but they are a lot more versatile than that. They can actually be created from pretty much anywhere, including from templates. One example can be found in the Layout.cshtml file of the ThemeMachine theme: WorkContext.Layout.Footer .Add(New.BadgeOfHonor(), "5"); .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; } What this is really doing is create a new shape called BadgeOfHonor and injecting it into the Footer global zone (that has not yet been defined, which in itself is quite awesome) with an ordering rank of "5". We can actually come up with something simpler, if we want to render the shape inline instead of sending it into a zone: @Display(New.BadgeOfHonor()) Now let's try something a little more elaborate and create a new shape for displaying a date and time: @Display(New.DateTime(date: DateTime.Now, format: "d/M/yyyy")) For the moment, this throws a "Shape type DateTime not found" exception because the system has no clue how to render a shape called "DateTime" yet. The BadgeOfHonor shape above was rendering something because there is a template for it in the theme: Themes/ThethemeMachine/Views/BadgeOfHonor.cshtml. We need to provide a template for our new shape to get rendered. Let's add a DateTime.cshtml file into our theme's Views folder in order to make the exception go away: Hi, I'm a date time shape. Now we're just missing one thing. Instead of displaying some static text, which is not very interesting, we can display the actual time that got passed into the shape's dynamic constructor. Those parameters will get added to the template's Model, so they are easy to retrieve: @(((DateTime)Model.date).ToString(Model.format)) Now that may remind you a little of WebForm's user controls. That's a fair comparison, except that these shapes are much more flexible (you can add properties on the fly as necessary), and that the actual rendering is decoupled from the "control". For example, any theme can override the template for a shape, you can use alternates, wrappers, etc. Most importantly, there is no lifecycle and protocol abstraction like there was in WebForms. I think this is a real improvement over previous attempts at similar things.

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  • InfoPath 2010 Form Design and Web Part Deployment

    - by JKenderdine
    In January I had the pleasure to speak at SharePoint Saturday Virginia Beach.  I presented a session on InfoPath 2010 forms design which included some of the basics of Forms Design, description of some of the new options with InfoPath 2010 and SharePoint 2010, and other integration possibilities.  Included below is the information presented as well as the solution to create the demo: First thing you need to understand is what the difference is between an InfoPath List form and a Form Library Form?  SharePoint List Forms:  Store data directly in a SharePoint list.  Each control (e.g. text box) in the form is bound to a column in the list. SharePoint list forms are directly connected to the list, which means that you don’t have to worry about setting up the publish and submit locations. You also do not have the option for back-end code. Form Library Forms:  Store data in XML files in a SharePoint form library.  This means they are more flexible and you can do more with them.  For example, they can be configured to save drafts and submit to different locations. However, they are more complex to work with and require more decisions to be made during configuration.  You do have the option of back-end code with these type of forms. Next steps: You need to create your File Architecture Plan.  Plan the location for the saved template – both Test and Production (This is pretty much a given, but just in case - Always make sure to have a test environment) Plan for the location of the published template Then you need to document your Form Template Design Plan.  Some questions to ask to gather your requirements: What will the form be designed to do? Will it gather user information? Will it display data from a data source? Do we need to show different views to different users? What do we base this on? How will it be implemented for the users? Browser or Client based form Site collection content type – Published through Central Admin Form Library – Published directly to form library So what are the requirements for this template?  Business Card Request Form Template Design Plan Gather user information and requirements for card Pull in as much user information as possible. Use data from the user profile web services as a data source Show and hide fields as necessary for requirements Create multiple views – one for those submitting the form and another view for the executive assistants placing the orders. Browser based form integrated into SharePoint team site Published directly to form library The form was published through Central Administration and incorporated into the site as a content type. Utilizing the new InfoPath Web part, the form is integrated into the page and the users can complete the form directly from within that page. For now, if you are interested in the final form XSN, contact me using the Contact link above.   I will post soon with the details on how the form was created and how it integrated the requirements detailed above.

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  • Apt-get update through tor

    - by Alexander
    I'm trying to update my apt-get list. In my country a lot of sites are blocked or have been blocked from companies. When I use a proxy for the whole system I get errors, tor works perfectly when browsing. My question is can I update apt-get through a connection from tor? I mean I want to unblock the blocked sites using tor connection so I can perform "apt-get update" without errors ... Thanks in advance. Edit BTW : I'm using Ubuntu 13.10 and Tor 0.2.21 alexander@Alexander-PC:~$ sudo apt-get update [sudo] password for alexander: Ign http://extras.ubuntu.com saucy InRelease Ign http://security.ubuntu.com saucy-security InRelease Ign http://us.archive.ubuntu.com saucy InRelease Hit http://extras.ubuntu.com saucy Release.gpg Get:1 http://dl.google.com stable InRelease [1,540 B] 100% [1 InRelease gpgv 1,540 B] [Waiting for headers] [Waiting for headers] [WaSplitting up/var/lib/apt/lists/partial/dl.google.com_linux_chrome_deb_dists_stabIgn http://dl.google.com stable InRelease E: GPG error: http://dl.google.com stable InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?

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  • Introducing MySQL for Excel

    - by Javier Treviño
    As part of the new product initiatives of the MySQL on Windows group we released a tool that makes the task of getting data in and out of a MySQL Database very friendly and intuitive, and we paired it with one of the preferred applications for data analysis and manipulation in Windows platforms, MS Excel. Welcome to MySQL for Excel, an add-in that is installed and accessed from within the MS Excel’s Data tab offering a wizard-like interface arranged in an elegant yet simple way to help users browse MySQL Schemas, Tables, Views and Procedures and perform data operations against them using MS Excel as the vehicle to drive the data in and out MySQL Databases. One of the coolest features we had in mind designing MySQL for Excel is simplicity. MS Excel is simple and easy to work with, thus liked by many Windows users because they don’t have to be software gurus to use it.  We applied the same principle by targeting MySQL for Excel to any kind of user, so if you are already familiarized with Excel’s interface you will find yourself working with MySQL data in no time. MySQL for Excel is shipped within the MySQL Installer as one of the tools in the suite; if prerequisites are already installed (.NET Framework 4.0, Visual Studio Tools for Office 4.0 and of course MS Office), installing the add-in involves a very few clicks and no further setup to use it. Being an Excel Add-In there is no executable file involved after the installation, running MS Excel and opening the add-in from its Data tab is all that is required. MySQL for Excel automatically integrates with MySQL Workbench (if installed) to share the same connections to MySQL Server installations, that way connections are defined just once in either product saving time.  Opening the Add-In brings the Welcome Panel at the right side of the Excel main window from which connections to MySQL Servers are shown grouped by Local VS Remote connections; then users can open any of those connections by double-clicking it and entering the password of the used account.  Additionally a user can create a connection by clicking on the New Connection action label or edit connections through MySQL Workbench (if installed) by clicking on the Manage Connections action label. Once a connection is opened, the Schema Selection panel is shown, at the top of it the selected connection (connection name, hostname/IP and username). Just below, a list of schemas is displayed where User Schemas are grouped first followed by System Schemas; users can double-click any selected schema to go to the next panel or select a schema and clicking the Next > button. Users can alternatively click on the < Back button to go back to the Welcome Panel to close the current connection and open a new one; also by clicking the Create New Schema action label they can create an empty new schema. Once a schema is opened the DB Object Selection panel is shown, this is actually the place where the fun stuff happens; from here users are able to perform actions against MySQL Tables, Views and Procedures. ">The actions available here are about importing data from a MySQL Table, View or Procedure to Excel, exporting Excel data to a new MySQL Table, appending Excel data to an existing MySQL Table or editing a MySQL Table’s data by using an Excel Worksheet as a user interface to update data in any row/column, insert new rows or delete existing rows in a very easy and friendly way. More blog posts will follow describing all of these actions, so stay tuned! Remember that your feedback is very important for us, so drop us a message: · MySQL on Windows (this) Blog - https://blogs.oracle.com/MySqlOnWindows/ · Forum - http://forums.mysql.com/list.php?172 · Facebook - http://www.facebook.com/mysql Cheers!

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  • Silverlight Cream for February 21, 2011 -- #1049

    - by Dave Campbell
    In this Issue: Rob Eisenberg(-2-), Gill Cleeren, Colin Eberhardt, Alex van Beek, Ishai Hachlili, Ollie Riches, Kevin Dockx, WindowsPhoneGeek(-2-), Jesse Liberty(-2-), and John Papa. Above the Fold: Silverlight: "Silverlight 4: Creating useful base classes for your views and viewmodels with PRISM 4" Alex van Beek WP7: "Google Sky on Windows Phone 7" Colin Eberhardt Shoutouts: My friends at SilverlightShow have their top 5 for last week posted: SilverlightShow for Feb 14 - 20, 2011 From SilverlightCream.com: Rob Eisenberg MVVMs Us with Caliburn.Micro! Rob Eisenberg chats with Carl and Richard on .NET Rocks episode 638 about Caliburn.Micro which takes Convention-over-Configuration further, utilizing naming conventions to handle a large number of data binding, validation and other action-based characteristics in your app. Two Caliburn Releases in One Day! Rob Eisenberg also announced that release candidates for both Caliburn 2.0 and Caliburn.Micro 1.0 are now available. Check out the docs and get the bits. Getting ready for Microsoft Silverlight Exam 70-506 (Part 6) Gill Cleeren has Part 6 of his series on getting ready for the Silverlight Exam up at SilverlightShow.... this time out, Gill is discussing app startup, localization, and using resource dictionaries, just to name a few things. Google Sky on Windows Phone 7 Colin Eberhardt has a very cool WP7 app described where he's using Google Sky as the tile source for Bing Maps, and then has a list of 110 Messier Objects.. interesting astronomical objects that you can look at... all with source! Silverlight 4: Creating useful base classes for your views and viewmodels with PRISM 4 Alex van Beek has some Prism4/Unity MVVM goodness up with this discussion of a login module using View and ViewModel base classes. Windows Phone 7 and WCF REST – Authentication Solutions Ishai Hachlili sent me this link to his post about WCF REST web service and authentication for WP7, and he offers up 2 solutions... from the looks of this, I'm also putting his blog on my watch list WP7Contrib: Isolated Storage Cache Provider Ollie Riches has a complete explanation and code example of using the IsolatedStorageCacheProvider in their WP7Contrib library. Using a ChannelFactory in Silverlight, part two: binary cows & new-born calves Kevin Dockx follows-up his post on Channel Factories with this part 2, expanding the knowledge-base into usin parameters and custom binding with binary encoding, both from reader suggestions. All about UriMapping in WP7 WindowsPhoneGeek has a post up about URI mappings in WP7 ... what it is, how to enable it in code behind or XAML, then using it either with a hyperlink button or via the NavigationService class... all with code. Passing WP7 Memory Consumption requirements with the Coding4Fun MemoryCounter tool WindowsPhoneGeek's latest is a tutorial on the use of the Memory Counter control from the Coding4Fun toolkit and WP7 Memory consumption. Getting Started With Linq Jesse Liberty gets into LINQ in his Episode 33 of his WP7 'From Scratch' series... looks like a good LINQ starting point, and he's going to be doing a series on it. Linq with Objects In his second post on LINQ, Jesse Liberty is looking at creating a Linq query against a collection of objects... always good stuff, Jesse! Silverlight TV Silverlight TV 62: The Silverlight 5 Triad Unplugged John Papa is joined by Sam George, Larry Olson, and Vijay Devetha (the Silverlight Triad) on this Silverlight TV episode 62 to discuss how the team works together, and hey... they're hiring! Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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  • Extreme Optimization – Numerical Algorithm Support

    - by JoshReuben
    Function Delegates Many calculations involve the repeated evaluation of one or more user-supplied functions eg Numerical integration. The EO MathLib provides delegate types for common function signatures and the FunctionFactory class can generate new delegates from existing ones. RealFunction delegate - takes one Double parameter – can encapsulate most of the static methods of the System.Math class, as well as the classes in the Extreme.Mathematics.SpecialFunctions namespace: var sin = new RealFunction(Math.Sin); var result = sin(1); BivariateRealFunction delegate - takes two Double parameters: var atan2 = new BivariateRealFunction (Math.Atan2); var result = atan2(1, 2); TrivariateRealFunction delegate – represents a function takes three Double arguments ParameterizedRealFunction delegate - represents a function taking one Integer and one Double argument that returns a real number. The Pow method implements such a function, but the arguments need order re-arrangement: static double Power(int exponent, double x) { return ElementaryFunctions.Pow(x, exponent); } ... var power = new ParameterizedRealFunction(Power); var result = power(6, 3.2); A ComplexFunction delegate - represents a function that takes an Extreme.Mathematics.DoubleComplex argument and also returns a complex number. MultivariateRealFunction delegate - represents a function that takes an Extreme.Mathematics.LinearAlgebra.Vector argument and returns a real number. MultivariateVectorFunction delegate - represents a function that takes a Vector argument and returns a Vector. FastMultivariateVectorFunction delegate - represents a function that takes an input Vector argument and an output Matrix argument – avoiding object construction  The FunctionFactory class RealFromBivariateRealFunction and RealFromParameterizedRealFunction helper methods - transform BivariateRealFunction or a ParameterizedRealFunction into a RealFunction delegate by fixing one of the arguments, and treating this as a new function of a single argument. var tenthPower = FunctionFactory.RealFromParameterizedRealFunction(power, 10); var result = tenthPower(x); Note: There is no direct way to do this programmatically in C# - in F# you have partial value functions where you supply a subset of the arguments (as a travelling closure) that the function expects. When you omit arguments, F# generates a new function that holds onto/remembers the arguments you passed in and "waits" for the other parameters to be supplied. let sumVals x y = x + y     let sumX = sumVals 10     // Note: no 2nd param supplied.     // sumX is a new function generated from partially applied sumVals.     // ie "sumX is a partial application of sumVals." let sum = sumX 20     // Invokes sumX, passing in expected int (parameter y from original)  val sumVals : int -> int -> int val sumX : (int -> int) val sum : int = 30 RealFunctionsToVectorFunction and RealFunctionsToFastVectorFunction helper methods - combines an array of delegates returning a real number or a vector into vector or matrix functions. The resulting vector function returns a vector whose components are the function values of the delegates in the array. var funcVector = FunctionFactory.RealFunctionsToVectorFunction(     new MultivariateRealFunction(myFunc1),     new MultivariateRealFunction(myFunc2));  The IterativeAlgorithm<T> abstract base class Iterative algorithms are common in numerical computing - a method is executed repeatedly until a certain condition is reached, approximating the result of a calculation with increasing accuracy until a certain threshold is reached. If the desired accuracy is achieved, the algorithm is said to converge. This base class is derived by many classes in the Extreme.Mathematics.EquationSolvers and Extreme.Mathematics.Optimization namespaces, as well as the ManagedIterativeAlgorithm class which contains a driver method that manages the iteration process.  The ConvergenceTest abstract base class This class is used to specify algorithm Termination , convergence and results - calculates an estimate for the error, and signals termination of the algorithm when the error is below a specified tolerance. Termination Criteria - specify the success condition as the difference between some quantity and its actual value is within a certain tolerance – 2 ways: absolute error - difference between the result and the actual value. relative error is the difference between the result and the actual value relative to the size of the result. Tolerance property - specify trade-off between accuracy and execution time. The lower the tolerance, the longer it will take for the algorithm to obtain a result within that tolerance. Most algorithms in the EO NumLib have a default value of MachineConstants.SqrtEpsilon - gives slightly less than 8 digits of accuracy. ConvergenceCriterion property - specify under what condition the algorithm is assumed to converge. Using the ConvergenceCriterion enum: WithinAbsoluteTolerance / WithinRelativeTolerance / WithinAnyTolerance / NumberOfIterations Active property - selectively ignore certain convergence tests Error property - returns the estimated error after a run MaxIterations / MaxEvaluations properties - Other Termination Criteria - If the algorithm cannot achieve the desired accuracy, the algorithm still has to end – according to an absolute boundary. Status property - indicates how the algorithm terminated - the AlgorithmStatus enum values:NoResult / Busy / Converged (ended normally - The desired accuracy has been achieved) / IterationLimitExceeded / EvaluationLimitExceeded / RoundOffError / BadFunction / Divergent / ConvergedToFalseSolution. After the iteration terminates, the Status should be inspected to verify that the algorithm terminated normally. Alternatively, you can set the ThrowExceptionOnFailure to true. Result property - returns the result of the algorithm. This property contains the best available estimate, even if the desired accuracy was not obtained. IterationsNeeded / EvaluationsNeeded properties - returns the number of iterations required to obtain the result, number of function evaluations.  Concrete Types of Convergence Test classes SimpleConvergenceTest class - test if a value is close to zero or very small compared to another value. VectorConvergenceTest class - test convergence of vectors. This class has two additional properties. The Norm property specifies which norm is to be used when calculating the size of the vector - the VectorConvergenceNorm enum values: EuclidianNorm / Maximum / SumOfAbsoluteValues. The ErrorMeasure property specifies how the error is to be measured – VectorConvergenceErrorMeasure enum values: Norm / Componentwise ConvergenceTestCollection class - represent a combination of tests. The Quantifier property is a ConvergenceTestQuantifier enum that specifies how the tests in the collection are to be combined: Any / All  The AlgorithmHelper Class inherits from IterativeAlgorithm<T> and exposes two methods for convergence testing. IsValueWithinTolerance<T> method - determines whether a value is close to another value to within an algorithm's requested tolerance. IsIntervalWithinTolerance<T> method - determines whether an interval is within an algorithm's requested tolerance.

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