Dynamic web pages are approachable in real time environment to user needs and desires, developing on the basis of input and distributing the information requested on the desirousness of the users. The means through which users make requests to and obtain output from the server is a Web Form that acts as intermediary among the interface of the user and the server. This form surrounds a variety of significant necessary types of server controls to pressure server processing. User obtained the input and validation and controls call upon sub-programs and functions to whole processing, output and information display controls are aim place on the page where scripts place their results for browser viewing, data source to supply information for processing and display, navigations controls a user send out data and processing requests to the server. The server in response produces output and inserts it on the webpage for release back to the user.
Here you will get overviews of different kinds of server controls available to produce dynamic, data-driven and user-responsive Web pages.
The <form> Tag
All Web Form controls are surround within a single <form> tag, generally encompassing the entire body of the HTML document. This tag is in the written in following format:
…server controls and XHTML code
A basic rule under ASP.NET is that Web Forms and their controls are server objects, not simply XHTML elements. This rule has been described by the fact that the <form> tag and its enclosed controls hold the specification Runat=”Server”. As server controls, these page elements are explicitly accessible via and interact with server scripts.
If you are already known with conservative forms processing, you will observe few misplaced attributes in the <form> tag. The action=”irl” attribute required for usual forms is not required and is disregarded if coded. The supposition is which form data are submitted to scripts on the few page as the form; they are posted back to that particular page. So, there is not necessary to indicate the same or other page as the destination for form data. The post technique coded on conventional forms is also assumed and require not be coded on server forms. Also possible is the name attribute. Form names are routinely assigned through ASP.NET for their own use.
It is important to remember that only one <form Runat=”Server”> tag can appear on a page. It is often convenient to code the opening tag immediately following the <body> tag, and to code the closing tag immediately preceding the </body> tag. In this fashion, the entire page becomes a form within which server controls can be placed anywhere on the page. A general outline for coding this XHTML portion of ASP.NET pages is shown below.
<?xml version=”1.0″ encoding=”UTF-8″?>
PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN”
<html xmlns=”http://www.w3.org/1999/xhtml” xml:lang=”en”>
<title>Any Web Page</title>
…Server controls and XHTML code
Listing 2-22. General page layout for a Web form.
Web forms enclose input, output, display, validation, navigation, data source, and script activation controls to carry out page processing activities. These various controls are summarized below and are described in detail in later tutorials.
There are server control equivalents to all of the XHTML form tags that appear on conventional forms, plus others. Some of these controls have the purpose of permitting user input into scripts, supplying data that scripts process, or making choices about script processing options. A standard textbox, for example, is coded on a conventional XHTML form as follows.
<input type=”text” name=”MyTextBox”/>