The Literal control is used to display text; that is, it renders static text on a Web page without adding additional HTML tags. It passes content directly to the client browser unless you use the Mode property to encode the content.
For the above reason, in some special place, we can use it freely, especially use the css class in our sorce
Here copy some sorce code from other web
Code for .aspx page
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:Literal ID="Literal1" runat="server" />
<asp:Literal ID="Literal2" runat="server" />
<asp:Literal ID="Literal3" runat="server" />
</div>
</form>
</body>
</html>
Code for .aspx.cs page
using System;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Literal1.Mode = LiteralMode.Encode;
Literal1.Mode = LiteralMode.PassThrough;
Literal1.Mode = LiteralMode.Transform;
Literal1.Text = @"<font size=4 color=red>Literal1 with Encode property example</font><script>alert(""Literal with Encode property"");</script></br></br>";
Literal2.Text = @"<font size=4 color=green>Literal2 with PassThrough property example</font><script>alert(""Literal with PassThrough property"");</script></br></br>";
Literal3.Text = @"<font size=4 color=blue>Literal3 with Encode Transform example</font><script>alert(""Literal with Transform property"");</script></br></br>";
}
}