Image.RenderContents(HtmlTextWriter) Method

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Renders the image control contents to the specified writer.

protected:
 override void RenderContents(System::Web::UI::HtmlTextWriter ^ writer);

protected public:
 override void RenderContents(System::Web::UI::HtmlTextWriter ^ writer);

protected override void RenderContents (System.Web.UI.HtmlTextWriter writer);

protected internal override void RenderContents (System.Web.UI.HtmlTextWriter writer);

override this.RenderContents : System.Web.UI.HtmlTextWriter -> unit

Protected Overrides Sub RenderContents (writer As HtmlTextWriter)

Protected Friend Overrides Sub RenderContents (writer As HtmlTextWriter)

Parameters

writer: HtmlTextWriter

An HtmlTextWriter that represents the output stream to render HTML content on the client.

Examples

The following code example demonstrates how to override the RenderContents method in a custom server control so that some text is always displayed after the Image.

<%@ 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 - RenderContents - C# Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom Image - RenderContents - C# Example</h3>
            
            <aspSample:CustomImageRenderContents 
              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 - RenderContents - VB.NET Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom Image - RenderContents - VB.NET Example</h3>
            
            <aspSample:CustomImageRenderContents 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 CustomImageRenderContents : System.Web.UI.WebControls.Image
  {
    protected override void RenderContents(System.Web.UI.HtmlTextWriter writer)
    {
      // Call the base RenderContents method.
      base.RenderContents(writer);

      // Append some text to the Image.
      writer.Write("<BR>Experience Windows Server 2003 and Visual Studio® .NET 2003.");
    }
  }
}

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

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

        ' Call the base RenderContents method.
        MyBase.RenderContents(writer)

        ' Append some text to the Image.
        writer.Write("<BR>Experience Windows Server 2003 and Visual Studio .NET 2003.")
    End Sub
End Class

Remarks

The RenderContents method is primarily used by control developers. The Image control implements the RenderContents method to skip rendering of any child controls.

Applies to

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