Image.RenderContents(HtmlTextWriter) 方法

定义

将图像控件内容呈现到指定的编写器。

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)

参数

writer
HtmlTextWriter

表示在客户端上呈现 HTML 内容的输出流的 HtmlTextWriter

示例

下面的代码示例演示如何重写 RenderContents 自定义服务器控件中的方法,以便某些文本始终显示在之后 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

注解

该方法 RenderContents 主要由控件开发人员使用。 该 Image 控件实现 RenderContents 方法以跳过任何子控件的呈现。

适用于

另请参阅