F9 Group Marketing and Technology Blog

jQuery is a lightweight, cross-browser JavaScript library designed to ease JavaScript’s most common tasks, including inspecting and manipulating the Document Object Model (DOM) and making out of band HTTP requests to support AJAX functionality. In plain English, jQuery makes it easy to perform client-side tasks like adding or removing attributes or CSS classes to elements in the DOM, or showing or hiding elements on the page in response to a user action (such as clicking a button). jQuery is used by many popular Web 2.0 sites to help implement rich, interactive features. jQuery can certainly be used in an ASP.NET application, although integrating client-side script into a Web Forms application can sometimes be a bit trying. JavaScript development fits more naturally with ASP.NET MVC applications; in fact, the ASP.NET MVC framework includes the jQuery libraries. What’s more, Microsoft has announced that jQuery will be included with Visual Studio 2010 and beyond . I recently had the opportunity to use jQuery in a intranet-based line of business Web Forms application. This application has a number of reporting screens that use a GridView control to display the report results. Users often want to filter the results to get a more concise snapshop of the data they are interested in, and to that end many of these reports include a filtering user interface, which is a series of drop-downs, checkboxes, and textboxes, through which they can apply various filtering criteria.

Microsoft’s ASP.NET AJAX framework offers two models for developing interactive web applications: client-centric and server-centric. With the server-centric model, developers use the standard ASP.NET controls – the GridView, Buttons, TextBoxes, and so forth – but place them within an UpdatePanel control . The UpdatePanel control automatically converts normal postbacks to partial page postbacks and seamlessly updates the page’s display with any modifications made by server-side code. On the other hand, with the client-centric model the developer is responsible for writing the JavaScript that performs any asynchronous requests to the server, as well as the script that updates the page on response. The server-centric model is easier to use and more familiar to developers who have a solid background with ASP.NET controls, but who are not as comfortable with JavaScript and HTML. However, that ease of use comes at a cost: the server-centric model shuttles a substantial amount of data between the client and server on each partial page postback. In short, the UpdatePanel sends the page’s view state to the server on a partial page postback and receives this (perhaps modified) view state back in response, regardless of whether the view state is needed to perform the server-side logic

By Quentin Zervaas. When you select elements from the Document Object Model (DOM) using the functions Prototype provides, each returned element is extended with extra functionality. In this, the second article in "Eight Weeks of Prototype," I will show you exactly how Prototype extends these elements.