Label Class (System.Web.UI.WebControls)

MSDN Library
.NET Development
.NET Framework 3.5
.NET Framework Class Library
System.Web.UI.WebControls Namespace

Label Class

Label Members
Label Constructor
Label Methods
Label Properties
Label Events

Related Links

Label Class
This page is specific to:.NET Framework Version:1.1 2.0 3.03.54.0

.NET Framework Class Library

Label Class

Represents a label control, which displays text on a Web page.

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

Syntax

C++

JScript

Copy to Clipboard Print

'Usage

Dim instance As Label

'Declaration

<ControlValuePropertyAttribute("Text")> _
<AspNetHostingPermissionAttribute(SecurityAction.InheritanceDemand, Level := AspNetHostingPermissionLevel.Minimal)> _
<AspNetHostingPermissionAttribute(SecurityAction.LinkDemand, Level := AspNetHostingPermissionLevel.Minimal)> _
Public Class Label _
    Inherits WebControl _
    Implements ITextControl

ASP.NET

<asp:Label />

Remarks

Use the Label control to display text in a set location on the page. Unlike static text, you can customize the displayed text through the Text property.

You can also use the Literal and PlaceHolder controls to display text on the Web Forms page. However, unlike the Label control, these controls do not render any additional tags.

Security Note:
This control can be used to display 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.

Accessibility

The markup rendered by default for this control might not conform to accessibility standards such as the Web Content Accessibility Guidelines 1.0 (WCAG) priority 1 guidelines. For details about accessibility support for this control, see ASP.NET Controls and Accessibility.

Topic	Location
How to: Add Controls to an ASP.NET Web Page Programmatically	Building ASP .NET Web Applications
How to: Add Controls to an ASP.NET Web Page Programmatically	Building ASP .NET Web Applications
How to: Add Controls to an ASP.NET Web Page Programmatically	Building ASP .NET Web Applications in Visual Studio
How to: Add Controls to an ASP.NET Web Page Programmatically	Building ASP .NET Web Applications in Visual Studio
How to: Add Label Web Server Controls to a Web Forms Page	Building ASP .NET Web Applications
How to: Add Label Web Server Controls to a Web Forms Page	Building ASP .NET Web Applications
How to: Add Label Web Server Controls to a Web Forms Page	Building ASP .NET Web Applications in Visual Studio
How to: Add Label Web Server Controls to a Web Forms Page	Building ASP .NET Web Applications in Visual Studio
How to: Add Label Web Server Controls to a Web Forms Page (Visual Studio)	Building ASP .NET Web Applications in Visual Studio
How to: Create Templates Dynamically in DataList Web Server Controls	Building ASP .NET Web Applications
How to: Create Templates Dynamically in DataList Web Server Controls	Building ASP .NET Web Applications
How to: Create Templates Dynamically in DataList Web Server Controls	Building ASP .NET Web Applications in Visual Studio
How to: Create Templates Dynamically in DataList Web Server Controls	Building ASP .NET Web Applications in Visual Studio
How to: Customize Individual Days in a Calendar Web Server Control	Building ASP .NET Web Applications
How to: Customize Individual Days in a Calendar Web Server Control	Building ASP .NET Web Applications
How to: Customize Individual Days in a Calendar Web Server Control	Building ASP .NET Web Applications in Visual Studio
How to: Customize Individual Days in a Calendar Web Server Control	Building ASP .NET Web Applications in Visual Studio
How to: Use Label Web Server Controls as Captions	Building ASP .NET Web Applications
How to: Use Label Web Server Controls as Captions	Building ASP .NET Web Applications
How to: Use Label Web Server Controls as Captions	Building ASP .NET Web Applications in Visual Studio
How to: Use Label Web Server Controls as Captions	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Control Designer for a Web Server Control	Authoring ASP.NET Controls
Walkthrough: Creating a Basic Control Designer for a Web Server Control	Authoring ASP.NET Controls
Walkthrough: Creating a Basic Control Designer for a Web Server Control	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Control Designer for a Web Server Control	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Web Page in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Web Page in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Web Page in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Web Page with Code Separation in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Web Page with Code Separation in Visual Web Developer	Building Applications with Visual Web Developer
Walkthrough: Creating a Basic Web Page with Code Separation in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating Accessible Web Pages	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating an Accessible Web Application	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating an Accessible Web Application	Building Applications with Visual Web Developer
Walkthrough: Creating and Using ASP.NET Master Pages in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating and Using ASP.NET Master Pages in Visual Web Developer	Building Applications with Visual Web Developer
Walkthrough: Creating and Using ASP.NET Master Pages in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Customizing a Web Site Using Themes	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Customizing a Web Site Using Themes	Building Applications with Visual Web Developer
Walkthrough: Customizing a Web Site Using Themes	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Data Binding to a Custom Business Object	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Data Binding to a Custom Business Object	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Data Binding to a Custom Business Object	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Validating User Input in a Web Forms Page	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Validating User Input in a Web Forms Page	Building Applications with Visual Web Developer
Walkthrough: Validating User Input in a Web Forms Page	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Working with Cascading Style Sheet Styles in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio

Examples

The following example demonstrates how to create a Label control on a Web page.

Note:
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 ASP.NET Web page code model, see ASP.NET Web Page Code Model.

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.

C++

JScript

Copy to Clipboard Print

<%@ Page Language="VB" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html  >
<head>
    <title>Label Example</title>
<script language="VB" runat="server">

      Sub Button_Click(Sender As Object, e As EventArgs) 
         Label1.Text = Server.HtmlEncode(Text1.Text)
      End Sub

   </script>

</head>

<body>

   <form id="Form1" runat="server">

      <h3>Label Example</h3>

      <asp:Label id="Label1" 
                 Text="Label Control" 
                 runat="server"/>

      <p>

      <asp:TextBox id="Text1" 
           Text="Copy this text to the label"
           Width="200px"  
           runat="server" />

      <asp:Button id="Button1" 
           Text="Copy" 
           OnClick="Button_Click" 
           runat="server"/>
      </p>
   </form>

</body>
</html>

.NET Framework Security

AspNetHostingPermission
for operating in a hosted environment. Demand value: LinkDemand; Permission value: Minimal.
AspNetHostingPermission
for operating in a hosted environment. Demand value: InheritanceDemand; Permission value: Minimal.

Inheritance Hierarchy

System..::.Object
  System.Web.UI..::.Control
    System.Web.UI.WebControls..::.WebControl
      System.Web.UI.WebControls..::.Label
        System.Web.UI.WebControls..::.BaseValidator

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

Reference

Label Members

System.Web.UI.WebControls Namespace

Text

Other Resources

Label Web Server Control Overview

Securing Standard Controls

How to: Protect Against Script Exploits in a Web Application by Applying HTML Encoding to Strings

Validating User Input in ASP.NET Web Pages

Community Content

Security issues

Added by:Thomas Lee

The documentation is badly worded with regards to security.

It states "This control can be used to display 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.".

ASP.NET validation will NOT help you here - only input is validated, not the rendered output of the Label control. It makes it seem as though you're safe including user-generated content in this control.

The contents of an <asp:Label> control are not "HTML Encoded" - if the control is used to display user-generated content (databound or otherwise) without first HTML Encoding it, the page has a serious security problem. Use <asp:Literal Mode="Encode"> instead, if possible.