Rick Strahl's Web Log

Recent Weblog Posts

RequestValidation Changes in ASP.NET 4.0
August 19, 2010 @ 1:40 pm

ASP.NET 4.0 changes the way request validation works by default, pushing request validation into the ASP.NET pipeline from the Web Forms engine. This might cause some unexpected behavior if you've used the validateRequest Page level attribute to allow unsafe content to be posted but it can also cause problems in other scenarios.

5 comments

Microsoft Introduces WebMatrix
August 17, 2010 @ 3:44 pm

Microsoft recently released a preview of WebMatrix a tool geared towards hobby/non-developer types to build Web applications. This all in one environment is supposed to simplify Web development with having to be an expert. In this post I review some of the interesting features and how they stack up.

8 comments

Debugging .NET 2.0 Assembly from unmanaged Code in VS2010
June 07, 2010 @ 12:58 pm

I’ve run into a serious snag trying to debug a .NET 2.0 assembly that is called from unmanaged code in Visual Studio 2010. I maintain a host of components that using COM interop and custom .NET runtime hosting and ever since installing Visual Studio 2010 I’ve been utterly blocked by VS 2010’s inability to apparently debug .NET 2.0 assemblies when launching through unmanaged code. Here’s what I’m...

7 comments

Non-Dom Element Event Binding with jQuery
May 27, 2010 @ 4:14 pm

jQuery makes it easy to bind events of DOM elements, but did you know that you can also bind to plain JavaScript function handlers with a little bit of extra work?

1 comment

What’s New in ASP.NET 4.0 Part Two: WebForms and Visual Studio Enhancements
May 04, 2010 @ 12:16 am

This article describes some of the useful new features in ASP.NET WebForms 4.0 as well some useful feature enhancements in Visual Studio specific to Web Development.

4 comments

What’s new in ASP.NET 4.0: Core Features
May 02, 2010 @ 4:35 am

Microsoft released the .NET Runtime 4.0 and with it comes a brand spanking new version of ASP.NET – version 4.0 – which provides an incremental set of improvements to an already powerful platform. .NET 4.0 is a full release of the .NET Framework, unlike version 3.5, which was merely a set of library updates on top of the .NET Framework version 2.0. Because of this full framework revision, there...

2 comments

DevConnections jQuery Session Slides and Samples posted
April 19, 2010 @ 1:55 pm

I've posted my slides and samples from the DevConnections VS 2010 Launch event last week in Vegas.

5 comments

AspNetCompatibility in WCF Services – easy to trip up
April 12, 2010 @ 3:51 pm

When using ASP.NET compatiblity in WCF REST services you'll want to be very careful in matching your configuration settings and service attributes in the correct combination or you may end up with unpleasant and hard to find ServiceActivationExceptions.

4 comments

No Preview Images in File Open Dialogs on Windows 7
March 10, 2010 @ 1:55 pm

I ran into a problem with a File Open dialog in Silverlight (but this applies to any Windows File Open Dialogs) where I could not get image previews to work. It turns out this setting is controlled by Explorer Customization settings which is a pain to figure out while tracking down the issue.

3 comments

.NET WebRequest.PreAuthenticate – not quite what it sounds like
February 18, 2010 @ 1:38 pm

On a few occasions I've dealt with Web Services that use - yuk - Basic Authentication and require pre-authentication on the very first request to the server with the server first sending a challenge. This is unusal for HTTP authentication which typically requires a challenge first and then a response with the auth information in the header. The latter approach is what the .NET client components produce by default. PreAuthenticate unfortunately is not quite true to its name and in order to provide true pre-authentication on the first request manual header manipulation is required.

6 comments

jQuery 1.4 Opacity and IE Filters
January 25, 2010 @ 12:42 am

Ran into a small compatibility issue with jQuery 1.4 where the $.css("opacity") function overwrites existing IE filter settings rather than additively applying them which has caused me a few problems with some components that heavily rely on opacity as well as a couple of other IE filters.

4 comments

HttpContext.Items and Server.Transfer/Execute
January 20, 2010 @ 4:32 pm

I got bitten by a the fact that the Context.Items collection stays active throughout the ENTIRE lifetime of an ASP.NET request including Server.Transfer and Execute calls. In certain situations this can cause big problems if you expect the items to be unique for the specific page/component request.

3 comments

Rendering ASP.NET Script References into the Html Header
January 02, 2010 @ 3:26 am

ASP.NET natively supports script embedding only into the body of the HTML document which is limited in many ways if you need more control over how scripts load under program control. In this post I'll show one of my components that allows embedding scripts and script references in the header of the document as well as many useful script embedding features for ASP.NET.

8 comments

LINQ to SQL and missing Many to Many EntityRefs
December 24, 2009 @ 2:05 am

LINQ to SQL expects every table to be mapped to have primary keys which is reasonable. However, today I ran into a problem with an existing database and a many to many relationship which did not have a Pk in the link table. The model and underlying XML seemed to map this just fine, however, the actual generated code did not approve of this arrangement.

12 comments

Making Sense of ASP.NET Paths
December 21, 2009 @ 1:20 am

ASP.NET includes a plethora of functions and utilities to retrieve information about the current requests and paths in general. So much so that it's often hard to remember exactly which path property or method you are actually looking for. This update to an old and very popular post from this blog summarizes many of the paths and path related operations that are available in ASP.NET.

38 comments

SmtpClient and Locked File Attachments
December 18, 2009 @ 3:00 pm

Ran into an easily overlooked problem a few days ago where SmtpClient messages with attachments would keep the attached files locked on the local machine. Email would send fine with attachments but the local files remain locked after sending. It's easy to miss as the files are locked for writing only so subsequent read operations actually work, but the file is still locked. The solution is easy enough by applying a .Dispose() in the right spot, but nonetheless unexpected.

9 comments

A free standing ASP.NET Pager Web Control
December 14, 2009 @ 12:15 am

Although there's decent Pager support in ASP.NET controls the way paging works is inconsistent and not very generic. After a recent experience of creating a small pager component for MVC I decided having a generic non-data or control dependent Pager WebControl would be useful. In this post I cover a custom Pager control implementation that addresses some of the shortcomings with the stock paging functionality for me.

15 comments

Visual Studio 2010 Beta 2 Startup Failures
December 05, 2009 @ 6:25 pm

I’ve been working with VS 2010 for a while now and while it works Ok most of the time it seems the environment is very, very fragile when it comes to crashes and installed packages. Specifically I’ve been working just fine for days, then when VS 2010 crashes it will not start. Instead I get the good old Application cannot start dialog: Other failures I’ve seen bring forth other just as useful...

7 comments

DevConnections Slides and Samples Posted
November 18, 2009 @ 4:54 am

I've posted my slides and samples from my 3 DevConnections sessions for you to download and check out.

8 comments

Capturing and Transforming ASP.NET Output with Response.Filter
November 13, 2009 @ 9:47 am

Capturing ASP.NET response output can be done in a variety of ways. In this post I'll discuss how you can use a Response.Filter to capture output and transform it using a simple class that provides event hooks to make it easy to capture output.

15 comments

$.fadeTo/fadeOut() operations on Table Rows in IE fail
November 09, 2009 @ 12:20 am

There's a rather sneaky bug in jQuery and Internet Explorer that causes jQuery's various fade methods like fadeIn/fadeOut/fadeTo to not work with table elements in any version of IE. The fade behavior doesn't have any effect on tables, rows, headers, but luckily the end result - a removed or visible element still works. Only the fade effect seems to go missing in action.

10 comments

ClientIDMode in ASP.NET 4.0
November 07, 2009 @ 3:58 pm

The new ClientIDMode in ASP.NET 4.0 is one of my most anticipated features to reduce the naming clutter that ASP.NET naming container naming has traditionally introduced into page. In this post I describe the ClientIDMode behavior and the various ways of how you can control ClientID generation with ASP.NET 4.0

22 comments

Ambiguous References in DefaultWsdlHelpGenerator.aspx
November 02, 2009 @ 5:52 pm

Ran into an odd problem today where the default ASMX Web Service help page was blowing up with DataBinding errors due to ambiguous class names. Turns out that a custom control with the same name as a System component and a static method call resulted in ambigous reference errors.

4 comments

No JavaScript IntelliSense in VS 2010 Beta 2? Reset your Settings
October 22, 2009 @ 2:52 pm

When I installed Visual Studio 2010 a couple of days ago I was really disappointed to see that Intellisense failed to work completely in the new install. No workey in .js files, or ASPX pages inside of script blocks. After some back and forth with folks on the ASPInsiders list and the product teams it looks like there is an issue somewhere with the default settings that get set when Visual Studio...

16 comments

A generic way to find ASP.NET ClientIDs with jQuery
October 15, 2009 @ 2:04 am

ASP.NET ClientIDs and NamingContainer naming are a nuisance when working with jQuery as these long IDs complicate finding elements on the page. In this post I show a very simple way to retrieve munged ClientIDs by just their ID names with a small helper function that still returns the jQuery wrapped set.

30 comments

LINQ to SQL, Lazy Loading and Prefetching
October 12, 2009 @ 2:56 am

Lazy loading in an ORM can be really useful or a royal pain if you walk through a lot of data. LINQ to SQL uses lazy loading of related entities and entity sets but there are a couple of ways that allow you to do eager loading instead. Both require some extra effort and foresight.

11 comments

Application that won’t Pin to Taskbar in Windows 7
October 08, 2009 @ 2:02 am

I've run into a dead end with an application of mine that won't pin to the Windows 7 taskbar. I've tried a number of different settings but I just cannot get the app to show the Pin to taskbar (or any othe of the taskbar context options) to work.

36 comments

Fun with Func<T,TResult> Delegates, Events and Async Operations
October 05, 2009 @ 1:38 am

Delegates are powerful for event handling, highly useful in LINQ and a core requirement for async operations. Func makes using delegate based logic a lot easier by providing a generic implemenation that in many cases allows you to skip creation of a separate delegate and instead just point at the Func definition which can be a big timesaver and a nice way to remove delegate defintions from your namespaces.

13 comments

Lookbehind in Regex searches
October 03, 2009 @ 2:03 am

Regex's more esoteric features are easy to miss as they make sense to me only in a context that applies to my work. I've certainly read about lookahead and lookbehind before but until I needed it today and was pointed to look at this functionality in the Regex engine it just didn't sink in. Lookbehind allows matching or not matching of a string before the the string you are interested in. It effectively allows you to look for values that don't have x before another match which is actually quite common.

8 comments

Debugger Visualizers not working in ASP.NET Medium Trust
September 24, 2009 @ 12:48 am

Debugger visualizers are quite useful for looking at common content while in the middle of debugging your application. However I've run into a number of problems with the debugger visualizer not popping up in ASP.NET applications due to the security environment. Turns out you need full trust in order to use debugger visualizers in ASP.NET applications.

2 comments

Integrating OpenID in an ASP.NET MVC Application using DotNetOpenAuth
September 17, 2009 @ 9:15 pm

OpenId is getting more popular and with it requests to integrate it into Web sites as a user authentication mechanism. In this post I'll discuss the OpenId integration on CodePaste.net in an ASP.NET MVC application disuccing both high level OpenId concepts, the process and the code implementation.

35 comments

Making jQuery calls to WCF/ASMX with a ServiceProxy Client
September 15, 2009 @ 8:31 pm

This post revisits the WCF/ASMX ServiceProxy that can be used to make native jQuery calls to ASMX and WCF AJAX services. The component is self contained and provides JSON conversions including dates, as well as a simple class interface for simple one line service calls and consistent error trapping. This is an update that handles native JSON parsers. Includes examples and a detailed walk through on how it works.

17 comments

jQuery UI Datepicker and z-Index
September 12, 2009 @ 8:12 pm

The jQuery UI datepicker is a nice and easy to use datepicker control but if you're using it with other components that use absolute positioning you might run into issues with z-Index precendence. Here's a discussion of the problem and a couple of easy solutions around it.

19 comments

Implementing a jQuery-Datepicker ASP.NET Control
September 10, 2009 @ 4:33 pm

Updated the jQueryDatePicker control from an old version of Mark Grabansiki's jQuery calendar to the latest version of jQuery.ui. This is an easy to use wrapper around the control to make it easy to drop the control onto a page with minimal configuration fuss and provide POST back functionality on the inline behavior.

20 comments

Get and Set Querystring Values in JavaScript
September 07, 2009 @ 2:12 am

Reading and writing query string values is often useful in Javascript code especially when dealing with client side initiatiated paging, sorting and ordering operations. If you need to modify the query string from the client before submitting the page it's nice to have a couple of small routines to do this easily. This short post demonstrates the setUrlEncodedKey and getUrlEncodedKey that do just that.

9 comments

Odd/Even Looping in ASP.NET MVC
August 31, 2009 @ 8:54 pm

Creating lists that have alternating display characteristics for alternating content are common and in MVC you have to do a little bit more work to make this happen. Here's an easy way to represent the expression using a boolean variable.

17 comments