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ImageButton.TagKey Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets the HtmlTextWriterTag value that corresponds to the ImageButton control.

protected:
 virtual property System::Web::UI::HtmlTextWriterTag TagKey { System::Web::UI::HtmlTextWriterTag get(); };
[System.ComponentModel.Browsable(false)]
protected override System.Web.UI.HtmlTextWriterTag TagKey { get; }
[<System.ComponentModel.Browsable(false)>]
member this.TagKey : System.Web.UI.HtmlTextWriterTag
Protected Overrides ReadOnly Property TagKey As HtmlTextWriterTag

Property Value

HtmlTextWriterTag

An HtmlTextWriterTag enumeration value.

Attributes
BrowsableAttribute

Examples

The following code example demonstrates how to override the TagKey method in a custom ImageButton control so that it always returns an Input tag.

Note

The following code sample uses the single-file code model and may not work correctly if copied directly into a code-behind file. The first part of the code sample must be copied into an empty text file that has an .aspx extension. The second part must be in a .cs file (for C#) or a .vb file (for Visual Basic). For more information on the Web Forms code model, see ASP.NET Web Forms Page Code Model.

<%@ 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 ImageButton - TagKey - C# Example</title>
    <script runat="server">
      void ImageButton1_Command(Object sender, CommandEventArgs e) 
      {
        // Redirect to the Microsoft home page.
        Response.Redirect("http://www.microsoft.com/");
      }
    </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom ImageButton - TagKey - C# Example</h3>
            
            <aspSample:CustomImageButtonTagKey 
              id="ImageButton1" 
              runat="server" 
              OnCommand="ImageButton1_Command" 
              AlternateText="Microsoft Home" 
              ImageUrl="http://www.microsoft.com/homepage/gif/bnr-microsoft.gif" />

        </form>
    </body>
</html>

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<%@ 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 xmlns="http://www.w3.org/1999/xhtml" >
    <head>
        <title>Custom ImageButton - TagKey - VB.NET Example</title>
        <script runat="server">
            Sub ImageButton1_Command(sender As Object, e As CommandEventArgs)
                ' Redirect to the Microsoft home page.
                Response.Redirect("http://www.microsoft.com/")
            End Sub
        </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom ImageButton - TagKey - VB.NET Example</h3>
            
            <aspSample:CustomImageButtonTagKey id="ImageButton1" runat="server" 
             OnCommand="ImageButton1_Command" AlternateText="Microsoft Home" 
             ImageUrl="http://www.microsoft.com/homepage/gif/bnr-microsoft.gif" />

        </form>
    </body>
</html>

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

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomImageButtonTagKey : System.Web.UI.WebControls.ImageButton
    {
        protected override System.Web.UI.HtmlTextWriterTag TagKey
        {
            get
            {
            // Specify that only the Input HTML tag can be passed to the HtmlTextWriter.
            return System.Web.UI.HtmlTextWriterTag.Input;
            }
        }
    }
}

<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomImageButtonTagKey
    Inherits System.Web.UI.WebControls.ImageButton

    Protected Overrides ReadOnly Property TagKey() As System.Web.UI.HtmlTextWriterTag
        Get
            ' Specify that only the Input HTML tag can be passed to the HtmlTextWriter.
            Return System.Web.UI.HtmlTextWriterTag.Input
        End Get
    End Property
End Class

Remarks

The TagKey property is used primarily by control developers when deriving a custom class from the ImageButton control.

Use the TagKey property to determine the HtmlTextWriterTag value associated with an ImageButton control. This property overrides the base implementation to always return HtmlTextWriterTag.Input.

Applies to

See also