CssClass Property

WebControl.CssClass Property


Gets or sets the Cascading Style Sheet (CSS) class rendered by the Web server control on the client.

Namespace:   System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)

public virtual string CssClass { get; set; }

Property Value

Type: System.String

The CSS class rendered by the Web server control on the client. The default is Empty.

Use the CssClass property to specify the CSS class to render on the client for the Web Server control. This property will render on browsers for all controls. It will always be rendered as the class attribute, regardless of the browser.

System_CAPS_security Security Note

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

For example, suppose you have the following Web server control declaration:

<asp:TextBox id="TextBox1" ForeColor="Red" CssClass="class1" />

The following HTML is rendered on the client for the previous Web server control declaration:

<input type=text class="class1" style="ForeColor:red">

If you use cascading style sheets (CSS) to customize the appearance of a control, use either inline styles or a separate CSS file, but not both. Using both inline styles and a separate CSS file could cause unexpected results.


On browsers that do not support CSS, setting the CssClass property will have no effect.

The following example illustrates how to use the CssClass property to change the style of a HyperLink control.


The following code sample uses the single-file code model and may not work correctly if copied directly into a code-behind file. This code sample must be copied into an empty text file that has an .aspx extension. For more information on the Web Forms code model, see ASP.NET Web Forms Page Code Model.

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 

<script runat="server">
    void Button1_Click(object sender, EventArgs e)
        if (HyperLink1.CssClass == "CssStyle1")
            HyperLink1.CssClass = "CssStyle2";
            HyperLink1.CssClass = "CssStyle1";

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head2" runat="server">
    <title>CssClass Property Example</title>
    <style type="text/css">
           font: 10pt Verdana; 
           color: Green;

           font: 15pt Times; 
           color: Blue;
    <form id="form1" runat="server">
        <h3>CssClass Property of a Web Control</h3>
        <asp:HyperLink id="HyperLink1" 
            Text="Click here to go to the Microsoft site" 
            Target="_new" runat="server" />
        <p><asp:Button id="Button1" 
            Text="Click to change the CSS style of the link"
            OnClick="Button1_Click" runat="server" />

.NET Framework
Available since 1.1
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