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Image.AddAttributesToRender(HtmlTextWriter) Method

  • Reference

Definition

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

Adds the attributes of an Image to the output stream for rendering on the client.

protected:
 override void AddAttributesToRender(System::Web::UI::HtmlTextWriter ^ writer);
protected override void AddAttributesToRender (System.Web.UI.HtmlTextWriter writer);
override this.AddAttributesToRender : System.Web.UI.HtmlTextWriter -> unit
Protected Overrides Sub AddAttributesToRender (writer As HtmlTextWriter)

Parameters

writer
HtmlTextWriter

A HtmlTextWriter that contains the output stream to render on the client browser.

Examples

The following code example demonstrates how to override the AddAttributesToRender method in a custom server control so that the Image always displays with a thin border.

<%@ 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 Image - AddAttributesToRender - C# Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom Image - AddAttributesToRender - C# Example</h3>
            
            <aspSample:CustomImageAddAttributesToRender 
              id="Image1" 
              runat="server" 
              ImageUrl="http://www.microsoft.com/homepage/gif/bnr-microsoft.gif" 
              AlternateText="Microsoft Home" />
            
        </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 Image - AddAttributesToRender - VB.NET Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom Image - AddAttributesToRender - VB.NET Example</h3>
            
            <aspSample:CustomImageAddAttributesToRender id="Image1" runat="server" 
             ImageUrl="http://www.microsoft.com/homepage/gif/bnr-microsoft.gif" 
             AlternateText="Microsoft Home" />
            
        </form>
    </body>
</html>

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

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomImageAddAttributesToRender : System.Web.UI.WebControls.Image
    {
        protected override void AddAttributesToRender(System.Web.UI.HtmlTextWriter writer)
        {
            // Show the Image with a thin border.
            writer.AddStyleAttribute("border-width","thin");

            // Call the Base's AddAttributesToRender method.
            base.AddAttributesToRender(writer);
        }
    }
}

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

    Protected Overrides Sub AddAttributesToRender(ByVal writer As System.Web.UI.HtmlTextWriter)

        ' Show the Image with a thin border.
        writer.AddStyleAttribute("border-width", "thin")

        ' Call the Base's AddAttributesToRender method.
        MyBase.AddAttributesToRender(writer)
    End Sub
End Class

Applies to