Rick Strahl's Web Log

Recent Weblog Posts

DropDownList and SelectListItem Array Item Updates in MVC
Wednesday @ 9:44 am

Ran into an 'interesting' behavior today with a cached list of SelectListItem[] in drop downlist where the cached list was getting updated by MVCs model binder.

8 comments

Passing multiple POST parameters to Web API Controller Methods
May 08, 2012 @ 10:29 pm

Web API allows for RPC style method access, but there are differences from older Microsoft AJAX APIs when it comes to passing multiple parameters. Here's how Web API handles parameters and how you can optionally manage multiple parameters to API Controller methods.

6 comments

Amazon Product Advertising API SOAP Namespace Changes
May 03, 2012 @ 4:36 am

Amazon recently broke their Product Advertising API by rolling out a new service version at the same URLs of the old service, which resulted in immediate failure of service. It's an easy fix once you know where to look. Here's how.

GZip/Deflate Compression in ASP.NET MVC
April 28, 2012 @ 4:00 am

If you want to create ASP.NET MVC content that uses gzip or deflate compression you need to use some custom code. Here's an action filter that compresses content in your ASP.NET MVC applications.

4 comments

Internet Explorer and Cookie Domains
April 25, 2012 @ 6:04 am

Got tripped up today by another IE issue: Internet Explorer will not accept Cookies with local domains set for the Cookie Domain and fail silently.

5 comments

Getting a 'base' Domain from a Domain
April 24, 2012 @ 9:17 pm

I was surprised to see that there wasn't some way in .Net to retrieve the base domain name from a sub-domain. For example, I want www.west-wind.com, and store.west-wind.com to return me just the base url. Easy enough but there are a couple small issues to check for especially when dealing with string based domain names.

9 comments

ASP.NET MVC Postbacks and HtmlHelper Controls ignoring Model Changes
April 20, 2012 @ 2:19 am

Today I discovered an MVC behavior I hadn't noticed: For HTML helper controls MVC always uses POSTBACK values to display the control value rather than model values when the View is rendering in a POST back. In effect this means that MVC Views can't update the value of controls during a POST back using the standard HTML Helper Controls.

16 comments

Wishful Thinking: Why can't HTML fix Script Attacks at the Source?
April 14, 2012 @ 5:49 pm

I'm dealing with user HTML input in a Web application today and again I curse over the complexities involved in sanitizing this html. So today I started dreaming about a possible alternative...

15 comments

Odd MVC 4 Beta Razor Designer Issue
April 14, 2012 @ 12:54 pm

I have an odd designer issue with MVC 4 Razor pages which are causing errors in the environment.

3 comments

Physical Directories vs. MVC View Paths
April 05, 2012 @ 2:38 pm

Physical directories that map paths that are also mapped by ASP.NET MVC routes can cause some consternation, especially if you're not aware that there's pathing overlap between the two. This post is a story about an operator error episode of an accidental file move that took a while to trace down due physical path interference.

4 comments

Creating a JSONP Formatter for ASP.NET Web API
April 02, 2012 @ 5:03 pm

Web API doesn't include native JSONP support, but it's pretty easy to create a custom formatter that handles this task. Here's how to create a JsonpFormatter and hook it up as well as a short review of how JSONP works.

5 comments

ASP.NET Web API and Simple Value Parameters from POSTed data
March 21, 2012 @ 5:05 pm

There are a few odd behaviors with Web API and its handling of simple parameters to Controller methods. While complex values serialize just fine, simple values like strings and dates and form variables require special attention.

7 comments

Dynamic JSON Parsing in .NET with JsonValue
March 19, 2012 @ 3:09 am

The JsonValue/JsonObject/JsonArray classes in the System.Json are new for the full .NET framework and recently introduced with the various betas of ASP.NET (and previously WCF) Web API. JsonValue fills the need for dynamically parsing and serializing of JSON at runtime.

12 comments

.NET 4.5 is an in-place replacement for .NET 4.0
March 13, 2012 @ 11:43 am

With the betas for .NET 4.5 and Visual Studio 11 and Windows 8 shipping many people will be installing .NET 4.5 and hacking away on it. There are a number of great enhancements that are fairly transparent, bBut it's important to understand what .NET 4.5 actually is in terms of the CLR running on your machine. When .NET 4.5 is installed it effectively replaces .NET 4.0 on the machine. .NET 4.0...

18 comments

Using an alternate JSON Serializer in ASP.NET Web API
March 09, 2012 @ 3:30 am

The default serializer in ASP.NET Web API (at least in Beta) is the DataContractJsonSerializer with all of its warts and inability to not serializer non-typed objects. In this post I'll talk about the issues and how to plug-in alternate JSON parsers to handle more complete JSON serialization in Web API.

14 comments

Removing the XML Formatter from ASP.NET Web API Applications
March 09, 2012 @ 1:51 am

When viewing ASP.NET Web API output in browsers the content is usually displayed as XML which is not my preferred choice. Even though JSON is Web APIs default format XML continues to be displayed. Here's some discussion on why this happens and how you can work around it.

9 comments

Using the HTML5 <input type="file" multiple="multiple"> Tag in ASP.NET
March 06, 2012 @ 1:54 am

HTML5 allows for multiple files to be uploaded from a single file input control. Here's how you can use it and capture files in ASP.NET.

5 comments

SnagIt Live Writer Plug-in updated
March 03, 2012 @ 5:07 pm

I've updated my SnagIt plug-in for Windows Live Writer to work with SnagIt 11. Also updated the user interface slightly and moved the source code to GitHub.

Make your CHM Help Files show HTML5 and CSS3 content
February 15, 2012 @ 2:17 pm

Want to get your CHM files to display content in HTML5 and CSS rather than the stock IE7 quirks more rendering used by default? This blog post describes how you can take advantage of newer HTML and CSS specs in your CHM files.

5 comments

Creating a dynamic, extensible C# Expando Object
February 08, 2012 @ 2:28 am

In this post I discuss a custom extensible dynamic type implementation that allows you to extend existing types with dynamic properties at runtime.

11 comments

Dynamic Types and DynamicObject References in C#
February 01, 2012 @ 2:47 am

This post explains the difference between dynamic reference and explicit references of an IDynamicObject implementation and how they behave differently.

6 comments

Unable to cast transparent proxy to type <type>
January 13, 2012 @ 1:25 pm

If you've ever run into the Unable to cast Transparent Proxy to error, you know how frustrating it can be. Usually this is caused by multiple assemblies causing unexpected load behaviors. Here's what the problem is and how you can check for problems.

2 comments

Problems with opening CHM Help files from Network or Internet
January 11, 2012 @ 12:13 am

Opening CHM files from a non-local location is no longer supported. Conveniently there's no decent error information displayed for this error so your first thought goes that there's something wrong with your help file. Here's an overview of the issue and some solutions on how to deal with it.

50 comments

IE9 not rendering box-shadow Elements inside of Table Cells
January 03, 2012 @ 6:44 pm

Looks like IE9 has a bug that won't render box-shadow CSS when the box-shadow is contained within a table that has border-collapse set. Here's what the problem is and how to work around it.

6 comments

XmlWriter and lower ASCII characters
January 02, 2012 @ 2:36 am

If you've ever tried to generate an XML document from content that contains lower ASCII characters you might have found out that this will throw exceptions. Here's why this happens and how you can work around the issue in a pinch.

3 comments

Changing the default HTML Templates to HTML5 in Visual Studio
December 23, 2011 @ 4:19 am

The default WebForms templates in Visual Studio still use the XHTML doctype headers by default. HTML5 doctype headers are easier to use and read and with HTML5 support now becoming mainstream and backward compatible with older browsers its time to switch those doctype headers. This post demonstrates how to change the default VS templates or create new templates altogether. With HTML becoming more prominent and the new headers being easier to read and smaller in size, it's

Debugging Application_Start and Module Initialization with IIS and Visual Studio
December 15, 2011 @ 2:19 am

If you're running the full version of IIS and you try to debug your Web application's startup code in Application_Start you might have found that you can't debug this code as the debugger doesn't break there. Here's why and some easy ways you can work around this limitation.

4 comments

HTML 5 Input Types - How useful is this really going to be?
December 10, 2011 @ 9:13 pm

The HTML 5 input controls enhancements seem like a nice feature - until you look a little closer and realize that that validation and styling these control enhancement use are likely going to interfere with your existing application logic and styling. Here are are some thoughts on the subject.

16 comments

HTML 5 Input Types on WebForms Controls
December 10, 2011 @ 8:24 pm

HTML5 input types are new, and as it turns out ASP.NET Webforms input controls can easily create HTML5 input elements.

5 comments

A Key Code Checker for DOM Keyboard Events
December 08, 2011 @ 3:47 am

Handling keyboard input events in JavaScript can be tricky when you need to deal with key codes. There are browser difference and different behaviors for various key events. Here's a refresher on how keyboard events work and a utility that lets you test key strokes and their resulting key codes in the various events available.

Creating a Dynamic DataReader for easier Property Access
December 06, 2011 @ 5:04 am

Custom dynamic types in .NET are great to wrap other data structures into easier to use and cleaner object.property interfaces. In this post I demonstrate how you can create a dynamic DataReader that allows access to a DataReader's fields using plain object.property syntax.

3 comments

jQuery Time Entry with Time Navigation Keys
November 30, 2011 @ 2:23 am

How do you display editable time values in Web applications? While date display has a pretty clear UI choice with date pickers, visual time picking isn't very efficient. In this post I show a keyboard based alternative to navigating and entering time (and date values) values using hotkeys hooked up through a jQuery plugin.

15 comments

Creating a Dynamic DataRow for easier DataRow Syntax
November 24, 2011 @ 3:13 am

The Dynamic Language Runtime features in .NET 4.0 make it very easy to create custom dynamic types that use alternate 'data sources' to expose a new member interface. In this post I describe a simple example that exposes a classic DataRow as a dynamic type to allow cleaner syntax and no need for type casting when accessing DataRow objects.

8 comments

Dynamically creating a Generic Type at Runtime
November 11, 2011 @ 4:39 am

How do you get a type reference to a generic type instance for a specific set of generic type parameters at runtime? Generics is primarily a coding time tool that creates code at compile time. It's not real easy to create generic types at runtime using dynamic type information. In this post I talk about an issue I ran into while trying to create dictionary types on the fly.

3 comments

Using the West Wind Web Toolkit to set up AJAX and REST Services
November 03, 2011 @ 4:55 am

In this post I describe how to use the West Wind Web Toolkit to create an AJAX/REST service that can serve data to a JavaScript applications with a few short steps. Then we'll look at ways to access the server side code with simple jQuery/JavaScript code and the ajaxCallMethod() helper.

10 comments

SnagIt Live Writer Plug-in Updated
October 13, 2011 @ 2:57 pm

I've updated my Live Writer SnagIt plugIn that provides screen captures to LiveWriter if you have TechSmith's SnagIt installed for professional looking screenshots directly from SnagIt into your Live Writer posts.

1 comment