Nikhil's WebDevHelper Utility and ASP.NET AJAX Support
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Nikhil is an architect on the ASP.NET Team and is constantly cooking up and posting cool new utilities and samples on his blog (all of which are of course free). Among his many projects is the Script# project, which is a C# compiler that generates JavaScript as its output instead of IL (allowing you to get type-safety, refactoring, and compile-time checking of your code). He also wrote the cool forward/back button support control for ASP.NET AJAX that I blogged about in September.
Earlier today he released an update to his popular WebDevHelper utility. Included within this release is support for easily monitoring the HTML updates that are returned from ASP.NET when using the <asp:updatepanel> control. His utility allows you to log and inspect all of the HTTP traffic between the browser and the server - making it much easier to debug AJAX code. For example, in the picture below you can see the HTML returned from an UpdatePanel when partial rendering is enabled on the page:
Nikhil has also recently added new support for inspecting JSON network requests and drilling into the objects serialized on the wire. For example, in the picture below you can see the properties for an "EXIF" picture object returned from the server via the ASP.NET AJAX Networking stack. Nikhil's utility automatically sniffs these on the client and allows you to easily inspect them:
He also has support for outputting trace statements as well as dumping objects from within JavaScript code using the WebDevHelper utility as well.
You can learn more about this free utility here, and read Nikhil's excellent documentation on how to use it here.
Hope this helps,
Scott