You’ve probably noticed that Jörn Zaefferer’s jQuery validation plugin has been gaining momentum in the ASP.NET community lately. Between Microsoft’s implied endorsement via ASP.NET MVC 2.0 integration and the plugin’s recent inclusion on the Microsoft AJAX CDN, adoption is only increasing. Unfortunately for those who don’t or can’t use ASP.NET MVC yet, using the validation plugin within WebForms applications can be tricky.

Because the WebForms Postback model requires that the entire page be contained within a single form element, form submissions that shouldn’t trigger validation are likely. ASP.NET’s built-in validation controls solve this with ValidationGroups and the CausesValidation property, but that doesn’t help if you’d prefer to use the jQuery validation plugin.

However, there are a couple relatively easy workarounds that make it possible to use the jQuery validation plugin on WebForms pages, without re-architecting the page or its forms. In this post, I’ll show you why the WebForms page structure is a problem, how to make jQuery validation work with it, and an example of implementing those workarounds.

Note: I want to preface this by saying that you should never rely entirely on client-side validation. The jQuery validation plugin can be a great replacement for the client-side part of the ASP.NET Validators, but it is not a complete replacement on its own. Use responsibly!

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By now, you probably already know that Google hosts jQuery on its AJAX APIs CDN, free of charge. As I’ve discussed here in the past, I’m a big fan of using their CDN to achieve decreased latency, increased parallelism, and better caching.

If you’ve explored the AJAX APIs documentation a bit, you may know that jQuery UI is also hosted on Google’s CDN. Unfortunately, since jQuery UI plugins depend on a ThemeRoller theme, using a CDN for jQuery UI isn’t as easy as with jQuery itself.

Or, is it?

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It was great to see all the positive responses to the screencast I recently recorded with Craig Shoemaker on how to use Firebug’s console to learn jQuery. That being my first screencast, I really appreciate all of your support.

However, you almost unanimously commented that it was too difficult to read the commands typed at the console, and you were right. So, Craig and I re-recorded the entire thing, paying extra attention to the legibility of the end result.

Craig also managed to edit the same content down to 9:59m this time, so you can watch it on YouTube if you prefer:

If the HQ version of the YouTube video still isn’t legible enough for you, Craig also made a full resolution WMV available as well.

While there’s no question that HTML, CSS, and JavaScript form the foundation of modern web development, achieving fluency hasn’t been easy for everyone. In particular, the transition from stateful development with pixel-precise layout – such as VB6 offered – has proven to be especially difficult. HTTP’s stateless nature and HTML’s relatively imprecise layout present a new, different set of challenges.

WebForms aspired to insulate us from those inconveniences. Promising rapid, drag ‘n drop layout and event-driven programming, WebForms was an attractive choice for anyone struggling with web development closer to the metal. Unfortunately, it has become apparent over the years that the WebForms abstraction, while convenient, can easily cause more problems than it solves.

More recently, Silverlight’s WYSIWYG layout and choice of familiar CLR languages have made it a similarly enticing alternative to HTML, CSS, and JavaScript among some .NET developers, but is history repeating itself? Are we leveraging Silverlight to move the platform forward or is it being used as another crutch?

Specifically, I want you to consider three areas that are negatively impacted by overzealous use of Silverlight: Usability, accessibility, and maintainability.

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Though the version number only inched up 0.0.1 with this release, it brings quite a few new features; most of them in response to your requests. I can’t include every request, but I will continue to improve the control based on your feedback, so keep them coming.

Changes in v4.1.5 include:

• Updated the base Highslide JS library to v4.1.5.
• Updated the embedded CSS to the latest version bundled with Highslide JS. This fixes the issue with the transparent/blank bar during enlargement if a caption is set.
• A few internal improvements that should make it work more reliably in some situations.

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UPDATE: We’ve recorded a higher quality version of this screencast.

When I hear that someone’s having trouble learning JavaScript or jQuery, my first suggestion to them is always the same: install Firebug and experiment at the console. Whether you’re an experienced JavaScript developer or haven’t written a single line of client-side code, the interactive nature of a command-line is one of the fastest ways to learn.

To demonstrate just how effective Firebug’s console can be, Craig Shoemaker and I recorded a short screencast on the topic. If you’re not taking advantage of this technique, be sure to take a minute (well, 16) and check it out:

http://polymorphicpodcast.com/podcast/video/firebug-and-jquery/

http://encosia.com/2009/09/21/updated-see-how-i-used-firebug-to-learn-jquery/

Question: Would you like to see more screencasts similar to this one?

If you’ve been reading long, you might remember that I’ve been a fan of ASP.NET AJAX in Action since the original was published. By avoiding heavy reliance on drag ‘n drop methodologies, the Manning book leaves readers with a deeper understanding of the framework.

Without understanding the underlying mechanisms well, developing successful solutions is as much a function of luck as it is skill; especially when it comes to debugging and maintenance. So, I think a comprehensive book like this is absolutely essential.

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As jQuery’s popularity in the .NET community has risen over the past year, one recurring theme I’ve seen is the desire to refactor away the details of using it to call ASP.NET AJAX services. Whether through helper function or specialized jQuery plugin, I’ve seen numerous methods proposed and/or in use.

Personally, the syntax never bothered me. The contentType parameter is ugly, but I have a Visual Studio code snippet for the $.ajax call and rarely think about it.

That came to an end earlier this year, when I started using dataFilter. I needed to isolate my code from the “.d” issue, and wanted to take advantage of browser-native JSON parsing in Firefox 3.5 and IE8, which required a bulky dataFilter.

Repeating that entire callback function in every $.ajax call was not acceptable. So, I was happy to learn that jQuery provides an excellent solution for consolidating settings to be used in multiple instances of $.ajax.

In this post, I’ll show you how to use that consolidation feature, and exactly how I am now using that to more simply call ASP.NET AJAX services with jQuery.

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When you’re working with JSON, performance and security are often opposing, yet equally important concerns. One of these areas of contention is handling the JSON strings returned by a server. Most JavaScript libraries do a great job of abstracting away the details, but the underlying process has long been a frustrating exercise in compromise.

On one hand, eval() is the fastest widely available method, but it is not safe.

On the other hand, textual JSON parsers written in JavaScript may be much safer, but are dramatically slower. In client-side situations, where milliseconds count, such a large performance overhead is typically too prohibitive to accept.

Recently, an exciting new alternative has emerged: browser-native JSON parsing. Integrating JSON parsing as part of the browser’s implementation of JavaScript allows for using the more secure parsing method, and even provides performance faster than eval() offers.

To take advantage of that, this post will show you how to detect whether or not a browser supports native JSON parsing, and how to force jQuery to use browser-native parsing in its $.ajax calls when it is available.

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When I recently received this message from a frustrated reader:

After hours and hours of slamming my head into the desk it turns out it was the darn "d" in the response. My home computer is on .NET 2.0 and my work computer is on 3.5. Jimminie Christmas!

I realized that the “.d” introduced in ASP.NET AJAX 3.5’s JSON responses is still all too common a stumbling block when calling ASP.NET AJAX services through a library such as jQuery. In fact, with jQuery’s popularity among ASP.NET developers on the rise, this appears to have become an even more frequent problem.

Since a lot of people are having trouble with it, I want to share one method you can use to completely isolate your code from the problem. If you bake this into an $.ajax() code snippet or otherwise use it as a template for calling ASP.NET AJAX services in jQuery, you should never have to think or worry about the “.d” again.

In this post, I will show you how to detect the “.d” and how you can completely isolate your $.ajax success handler from it.

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