ASP.NET Web Forms - HTML Forms

All server controls must appear within a <form> tag, and the <form> tag must include the runat="server" attribute.

ASP.NET Web Forms

All server controls must appear within a <form> tag, and the <form> tag must include the runat="server" attribute. The runat="server" attribute indicates that the form must be processed on the server. It also indicates that the controls contained within it can be accessed by server scripts:

<form runat="server">

...HTML + server controls

</form>

Note:The form is always submitted to its own page. If you specify an action attribute, it will be ignored. If you omit the method attribute, it will default to method="post". Also, if you do not specify the name and id attributes, they will be automatically assigned by ASP.NET.

Note:An .aspx page can only contain one <form runat="server"> control!

If you choose to view the source code in an .aspx page that contains a form without the name, method, action, or id attributes, you will see that ASP.NET has added these attributes to the form, as shown below:

<form name="_ctl0" method="post" action="page.aspx" id="_ctl0">

...some code

</form>

Submit Form

Forms are usually submitted by clicking a button. The format of the Button server control in ASP.NET is as follows:

<asp:Button id="id" text="label" OnClick="sub" runat="server" />

The id attribute defines a unique name for the button, and the text attribute assigns a label to the button. The onClick event handler specifies a named subroutine to be executed.

In the following example, we declare a button control in an .aspx file. A single mouse click can run a subroutine that can change the text on the button.

Example

Other Extensions