WebControl.Enabled Property (System.Web.UI.WebControls)

Enabled Property

.NET Framework Class Library

WebControl..::.Enabled Property

Gets or sets a value indicating whether the Web server control is enabled.

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

Syntax

Visual Basic (Declaration)

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

Visual Basic (Usage)

Dim instance As WebControl
Dim value As Boolean

value = instance.Enabled

instance.Enabled = value

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

Visual C++

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

JScript

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

ASP.NET

<asp:WebControl Enabled="True|False" />

Property Value

Type: System..::.Boolean
true if control is enabled; otherwise, false. The default is true.

Remarks

Use the Enabled property to specify or determine whether a control is functional. When set to false, the control appears dimmed, preventing any input from being entered in the control.

Note:
Not all browsers support this property. Dimming and locking the control only works in browsers that are compatible with Microsoft Internet Explorer version 4 and later.

This property propagates down the control hierarchy. Therefore, disabling a container control will disable all child controls within that container.

Note:
In a custom composite control, this behavior does not apply to controls that have not yet created their child controls. You must either set the enabled state of the child controls when they are created, or override the Enabled property to call the EnsureChildControls method.

Note:
A disabled control can support postbacks. It is possible for a user who is viewing the page with a disabled control to craft a request that submits a postback that is processed by the page. Prior to processing a postback request, check to make sure that the control is enabled and visible.

Not all controls support this property. See the individual controls for details.

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

Topic	Location
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

Examples

The following example illustrates how to enable and disable a TextBox control, inherited from the WebControl base class, by setting its Enabled property programmatically.

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 Web Forms 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.

Visual Basic

<%@ Page Language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">
    Sub SubmitBtn1_Click(ByVal sender As Object, ByVal e As EventArgs)
        TextBox1.Enabled = Not (TextBox1.Enabled)
    End Sub
</script>

<html  >
<head id="Head2" runat="server">
    <title>Enabled Property Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h3>Enabled Property of a Web Control</h3>
            <p>
                <asp:TextBox id="TextBox1" BackColor="LightBlue" 
                    runat="server">Light Blue</asp:TextBox>
            </p>
            <p>
                <asp:TextBox id="TextBox2" BackColor="LightGreen" 
                    runat="server">Light Green</asp:TextBox>
            </p>
            <asp:Button id="SubmitBtn1" runat="server"
                Text="Click to disable or enable the light blue text box" 
                OnClick="SubmitBtn1_Click" />
    </div>
    </form>
</body>
</html>

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

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">
    void SubmitBtn1_Click(object sender, EventArgs e)
    {
        TextBox1.Enabled = (!TextBox1.Enabled);
    }
</script>

<html  >
<head id="Head2" runat="server">
    <title>Enabled Property Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h3>Enabled Property of a Web Control</h3>
            <p>
                <asp:TextBox id="TextBox1" BackColor="LightBlue" 
                    runat="server">Light Blue</asp:TextBox>
            </p>
            <p>
                <asp:TextBox id="TextBox2" BackColor="LightGreen" 
                    runat="server">Light Green</asp:TextBox>
            </p>
            <asp:Button id="SubmitBtn1" runat="server"
                Text="Click to disable or enable the light blue text box" 
                OnClick="SubmitBtn1_Click" />
    </div>
    </form>
</body>
</html>

JScript

<%@ Page Language="JScript" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    function SubmitBtn1_Click(sender : Object, e : EventArgs)
    {
        TextBox1.Enabled = !TextBox1.Enabled
    }

</script>

<html  >
<head id="Head2" runat="server">
    <title>Enabled Property Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h3>Enabled Property of a Web Control</h3>
            <p>
                <asp:TextBox id="TextBox1" BackColor="LightBlue" 
                    runat="server">Light Blue</asp:TextBox>
            </p>
            <p>
                <asp:TextBox id="TextBox2" BackColor="LightGreen" 
                    runat="server">Light Green</asp:TextBox>
            </p>
            <asp:Button id="SubmitBtn1" runat="server"
                Text="Click to disable or enable the light blue text box" 
                OnClick="SubmitBtn1_Click" />
    </div>
    </form>
</body>
</html>

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

WebControl Class

WebControl Members

System.Web.UI.WebControls Namespace

EnsureChildControls

Other Resources

ASP.NET Web Server Controls and Browser Capabilities

Web Server Control Syntax

Developing Custom ASP.NET Server Controls