Book Image

ASP.NET jQuery Cookbook - Second Edition

By : Sonal Aneel Allana
Book Image

ASP.NET jQuery Cookbook - Second Edition

By: Sonal Aneel Allana

Overview of this book

jQuery is a lightweight JavaScript library that has changed the landscape of client scripting in web applications. Developed by John Resig in 2006, it has taken the web by storm because of its cross-browser compatibility and the ability to get more done with less code. It has gained popularity with ASP.NET developers and is now distributed with Visual Studio and the NuGet package manager. ASP.NET jQuery Cookbook explores the wide range of utilities that the jQuery library provides. It teaches you the nitty-gritty of plugging in these features in ASP.NET web applications. It covers every aspect of interfacing the library, right from downloading and including jQuery on web pages to selecting controls, handling events, and creating animations. This book also walks you through DOM traversal and manipulation in ASP.NET and then through visual effects and graphics in ASP.NET sites. It explores advanced features such as posting AJAX requests and writing plugins. It will provide you with all the information you need to use this library confidently with ASP.NET.
Table of Contents (15 chapters)
ASP.NET jQuery Cookbook Second Edition
About the Author
About the Reviewer

Adding jQuery programmatically to a web form

In addition to adding jQuery to web forms using the script block and the ScriptManager control, the code-behind file can also emit the required script code. This recipe will demonstrate how this can be done.

Getting ready

  1. Create an ASP.NET Web Application project by navigating to File | New | Project | ASP.NET Web Application. Select the Empty template. Name the project WebApplicationWithPageLoad (or any other suitable name).

  2. Add a new Web Form to the project and name it Default.aspx.

  3. Add the jQuery library files to the Scripts folder.

  4. From the Solution Explorer tab, navigate to Default.aspx.vb (VB) or Default.aspx.cs (C#), which is the code-behind file for the web form. Open this file.

How to do it…

In the Page_Load event handler of Default.aspx.vb, use the RegisterClientScriptInclude method to generate a script block on the page, as follows:

For VB, the code is as follows:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
   Page.ClientScript.RegisterClientScriptInclude("jquery",   Page.ResolveUrl("~/Scripts/jquery-2.1.4.js"))
End Sub

For C#, the code is as follows:

protected void Page_Load(object sender, EventArgs e)
   Page.ClientScript.RegisterClientScriptInclude("jquery",   Page.ResolveUrl("~/Scripts/jquery-2.1.4.js"));

How it works…

The RegisterClientScriptInclude method requires two parameters: the key and URL. It adds the script block with the path to the jQuery library in the <form> element, as shown in the following screenshot. The Page.ResolveUrl method is used to return a URL relative to the site root:

Since the jQuery library is added to the <form> element, all the jQuery code should be written in the <form> element instead of the <head> element, preferably toward the end of the page before closing the <form> element.

See also

The Adding jQuery to an empty ASP.NET web project using a script block recipe