Image.RenderContents(HtmlTextWriter) Metodo
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Esegue il rendering del contenuto del controllo immagine nel writer specificato.
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)
Parametri
- writer
- HtmlTextWriter
Oggetto HtmlTextWriter che rappresenta il flusso di output per il rendering del contenuto HTML nel client.
Esempio
Nell'esempio di codice seguente viene illustrato come eseguire l'override del RenderContents metodo in un controllo server personalizzato in modo che un testo venga sempre visualizzato dopo .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
Commenti
Il RenderContents metodo viene usato principalmente dagli sviluppatori di controlli. Il Image controllo implementa il metodo per ignorare il RenderContents rendering di tutti i controlli figlio.