TextBox.TagKey Property

Gets the HTML tag for the text box control. This property is protected.

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

protected override HtmlTextWriterTag TagKey { get; }
/** @property */
protected HtmlTextWriterTag get_TagKey ()

protected override function get TagKey () : HtmlTextWriterTag

Not applicable.

Property Value

HtmlTextWriterTag.Textarea if the text box is multiline; otherwise, Input.

The following code example demonstrates how to use the Tagkey property to create a custom text box.

Security noteSecurity 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 (Visual Studio).

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<%@ Page Language="C#" AutoEventWireup="True" %>
<!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>
        <title>Custom TextBox - TagKey - C# Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom TextBox - TagKey - C# Example</h3>
            
            <aspSample:CustomTextBoxTagKey 
              id="TextBox1" 
              runat="server">Hello World!
            </aspSample:CustomTextBoxTagKey>
            
        </form>
    </body>
</html>

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.JSL.Controls" Assembly="Samples.AspNet.JSL" %>
<%@ Page Language="VJ#" AutoEventWireup="True" %>
<!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>
        <title>Custom TextBox - TagKey - VJ# Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom TextBox - TagKey - VJ# Example</h3>
            
            <aspSample:CustomTextBoxTagKey 
              id="TextBox1" 
              runat="server"
              text="Hello World!">
            </aspSample:CustomTextBoxTagKey>
            
        </form>
    </body>
</html>

using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand, Level=AspNetHostingPermissionLevel.Minimal)]
  public sealed class CustomTextBoxTagKey : System.Web.UI.WebControls.TextBox
  {
    protected override System.Web.UI.HtmlTextWriterTag TagKey
    {
      get 
      {
        // If the TextMode is MultiLine, return a Textarea tag, 
        // else return an Input tag.
        if (this.TextMode == System.Web.UI.WebControls.TextBoxMode.MultiLine)
        {
          return System.Web.UI.HtmlTextWriterTag.Textarea;
        }
        else
        {
          return System.Web.UI.HtmlTextWriterTag.Input;
        }
      }
    }
  }
}

package Samples.AspNet.JSL.Controls; 

public class CustomTextBoxTagKey
    extends System.Web.UI.WebControls.TextBox
{
    /** @property 
     */
    protected System.Web.UI.HtmlTextWriterTag get_TagKey()
    {
        // If the TextMode is MultiLine, return a Textarea tag, 
        // else return an Input tag.
        if (this.get_TextMode().Equals(System.Web.UI.WebControls.
            TextBoxMode.MultiLine)) {
            return System.Web.UI.HtmlTextWriterTag.Textarea;
        }
        else {
            return System.Web.UI.HtmlTextWriterTag.Input;
        }
    } //get_TagKey
} //CustomTextBoxTagKey

Windows 98, Windows Server 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

Community Additions

ADD
Show: