TextBox.ReadOnly Property (System.Web.UI.WebControls)

ReadOnly Property

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This page is specific to

Microsoft Visual Studio 2008/.NET Framework 3.5

Other versions are also available for the following:

.NET Framework Class Library

TextBox..::.ReadOnly Property

Updated: November 2007

Gets or sets a value indicating whether the contents of the TextBox control can be changed.

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

Syntax

Visual Basic (Declaration)

<BindableAttribute(True)> _
<ThemeableAttribute(False)> _
Public Overridable Property ReadOnly As Boolean

Visual Basic (Usage)

Dim instance As TextBox
Dim value As Boolean

value = instance.ReadOnly

instance.ReadOnly = value

[BindableAttribute(true)]
[ThemeableAttribute(false)]
public virtual bool ReadOnly { get; set; }

Visual C++

[BindableAttribute(true)]
[ThemeableAttribute(false)]
public:
virtual property bool ReadOnly {
    bool get ();
    void set (bool value);
}

/** @property */
/** @attribute BindableAttribute(true) */
/** @attribute ThemeableAttribute(false) */
public boolean get_ReadOnly()
/** @property */
/** @attribute BindableAttribute(true) */
/** @attribute ThemeableAttribute(false) */
public  void set_ReadOnly(boolean value)

JScript

public function get ReadOnly () : boolean
public function set ReadOnly (value : boolean)

ASP.NET

<asp:TextBox ReadOnly="True|False" />

Property Value

Type: System..::.Boolean

true if the contents of the TextBox control cannot be changed; otherwise, false. The default value is false.

Remarks

Use the ReadOnly property to specify whether the contents of the TextBox control can be changed. Setting this property to true will prevent users from entering a value or changing the existing value. Note that the user of the TextBox control cannot change this property; only the developer can.

Important Note:
The Text value of a TextBox control with the ReadOnly property set to true is sent to the server when a postback occurs, but the server does no processing for a read-only text box. This prevents a malicious user from changing a Text value that is read-only. The value of the Text property is preserved in the view state between postbacks unless modified by server-side code.

This property cannot be set by themes or style sheet themes. For more information, see ThemeableAttribute and ASP.NET Themes and Skins Overview.

Examples

The following code example demonstrates how to use the ReadOnly property to prevent any changes to the text displayed in the TextBox control.

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.

Visual Basic

<%@ 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> MultiLine TextBox Example </title>
<script runat="server">

      Protected Sub SubmitButton_Click(sender As Object, e As EventArgs )

         Message.Text = "Thank you for your comment: <br />" + Comment.Text

      End Sub

      Protected Sub Check_Change(sender As Object, e As EventArgs )

         Comment.Wrap = WrapCheckBox.Checked
         Comment.ReadOnly = ReadOnlyCheckBox.Checked

      End Sub

   </script>

</head>

<body>

   <form id="form1" runat="server">

      <h3> MultiLine TextBox Example </h3>


      Please enter a comment and click the submit button. 

      <br /><br /> 

      <asp:TextBox ID="Comment"
           TextMode="MultiLine"
           Columns="50"
           Rows="5"
           runat="server"/>

      <br />

      <asp:RequiredFieldValidator
           ID="Value1RequiredValidator"
           ControlToValidate="Comment"
           ErrorMessage="Please enter a comment.<br />"
           Display="Dynamic"
           runat="server"/>                         

      <asp:CheckBox ID="WrapCheckBox"
           Text="Wrap Text"
           Checked="True"
           AutoPostBack="True"
           OnCheckedChanged="Check_Change"
           runat="server"/>

      &nbsp;&nbsp;

      <asp:CheckBox ID="ReadOnlyCheckBox"
           Text="ReadOnly"
           Checked="False"
           AutoPostBack="True"
           OnCheckedChanged="Check_Change"
           runat="server"/>

      &nbsp;&nbsp;

      <asp:Button ID="SubmitButton"
           Text="Submit"
           OnClick="SubmitButton_Click"
           runat="server"/>

      <hr />

      <asp:Label ID="Message"
           runat="server"/>

   </form>

</body>
</html>

<%@ 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  > 

<head>
    <title> MultiLine TextBox Example </title>
<script runat="server">

      protected void SubmitButton_Click(Object sender, EventArgs e)
      {

         Message.Text = "Thank you for your comment: <br />" + Comment.Text;

      }

      protected void Check_Change(Object sender, EventArgs e)
      {

         Comment.Wrap = WrapCheckBox.Checked;
         Comment.ReadOnly = ReadOnlyCheckBox.Checked;

      }

   </script>

</head>

<body>

   <form id="form1" runat="server">

      <h3> MultiLine TextBox Example </h3>


      Please enter a comment and click the submit button. 

      <br /><br /> 

      <asp:TextBox ID="Comment"
           TextMode="MultiLine"
           Columns="50"
           Rows="5"
           runat="server"/>

      <br />

      <asp:RequiredFieldValidator
           ID="Value1RequiredValidator"
           ControlToValidate="Comment"
           ErrorMessage="Please enter a comment.<br />"
           Display="Dynamic"
           runat="server"/>                         

      <asp:CheckBox ID="WrapCheckBox"
           Text="Wrap Text"
           Checked="True"
           AutoPostBack="True"
           OnCheckedChanged="Check_Change"
           runat="server"/>

      &nbsp;&nbsp;

      <asp:CheckBox ID="ReadOnlyCheckBox"
           Text="ReadOnly"
           Checked="False"
           AutoPostBack="True"
           OnCheckedChanged="Check_Change"
           runat="server"/>

      &nbsp;&nbsp;

      <asp:Button ID="SubmitButton"
           Text="Submit"
           OnClick="SubmitButton_Click"
           runat="server"/>

      <hr />

      <asp:Label ID="Message"
           runat="server"/>

   </form>

</body>
</html>

Platforms

Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, 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