Page.CreateHtmlTextWriter(TextWriter) Metodo

Definizione

Spazio dei nomi:

System.Web.UI

Assembly:

System.Web.dll

Crea un HtmlTextWriter oggetto per il rendering del contenuto della pagina.

protected public:
 virtual System::Web::UI::HtmlTextWriter ^ CreateHtmlTextWriter(System::IO::TextWriter ^ tw);

protected internal virtual System.Web.UI.HtmlTextWriter CreateHtmlTextWriter(System.IO.TextWriter tw);

abstract member CreateHtmlTextWriter : System.IO.TextWriter -> System.Web.UI.HtmlTextWriter
override this.CreateHtmlTextWriter : System.IO.TextWriter -> System.Web.UI.HtmlTextWriter

Protected Friend Overridable Function CreateHtmlTextWriter (tw As TextWriter) As HtmlTextWriter

Parametri

tw

TextWriter

Oggetto TextWriter utilizzato per creare l'oggetto HtmlTextWriter.

Restituisce

HtmlTextWriter

Oggetto HtmlTextWriter o Html32TextWriter.

Esempio

Nell'esempio di codice seguente viene usato il CreateHtmlTextWriter metodo per creare un'istanza di un oggetto personalizzato HtmlTextWriter denominato MyHtmlTextWriter. Il CreateHtmlTextWriter metodo viene sottoposto a override nella MyPage classe , derivata da Page, in modo che MyHtmlTextWriter esegua il rendering dei controlli server ASP.NET quando viene richiesta la pagina. Si noti che questo esempio impedirà il comportamento dell'adattatore TextWriter .

namespace WebPage
{
   using System;
   using System.IO;
   using System.Web.UI;

   public class MyPage : Page
   {
      public MyPage():base()
      {
      }

      [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] 
      protected override HtmlTextWriter CreateHtmlTextWriter(TextWriter writer)
      {
         return new MyHtmlTextWriter(writer);
      }

      [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] 
      protected override void Render(HtmlTextWriter writer)
      {         
         // Write a Font control.
         writer.AddAttribute("color", "red");
         writer.AddAttribute("size", "6pt");
         writer.RenderBeginTag(HtmlTextWriterTag.Font);
         writer.Write("<br>" + "The time on the server:<br> " + System.DateTime.Now.ToLongTimeString());
         writer.RenderEndTag();
      }
   }

   public class MyHtmlTextWriter : HtmlTextWriter
   {
      public MyHtmlTextWriter(TextWriter writer):base(writer)
      {
         writer.Write("<font color=blue> 'MyHtmlTextWriter' is used for rendering.</font>");
      }
   }
}

Imports System.IO
Imports System.Web.UI

Namespace WebPage

    
   Public Class MyPage
      Inherits Page
      
      Public Sub New()
         MyBase.New()
      End Sub

      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
      Protected Overrides Function CreateHtmlTextWriter(ByVal writer As TextWriter) As HtmlTextWriter
         Return New MyHtmlTextWriter(writer)
      End Function 'CreateHtmlTextWriter

      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
      Protected Overrides Sub Render(ByVal writer As HtmlTextWriter)
         ' Writes a Font control.
         writer.AddAttribute("color", "red")
         writer.AddAttribute("size", "6pt")
         writer.RenderBeginTag(HtmlTextWriterTag.Font)
         writer.Write(("<br>" + "The time on the server:<br> " + System.DateTime.Now.ToLongTimeString()))
         writer.RenderEndTag()
      End Sub
   End Class
    

   Public Class MyHtmlTextWriter
      Inherits HtmlTextWriter
      
      Public Sub New(writer As TextWriter)
         MyBase.New(writer)
         writer.Write("<font color=blue> 'MyHtmlTextWriter' is used for rendering.</font>")
      End Sub
   End Class
End Namespace 'WebPage

Commenti

Il CreateHtmlTextWriter metodo crea un oggetto TextWriter tramite la Browser proprietà dell'oggetto Request associato alla richiesta di pagina. È possibile aggiungere un riferimento a un HtmlTextWriter nella browserCaps sezione di configurazione. Eseguire l'override del CreateHtmlTextWriter metodo per eseguire una ricerca personalizzata.

Vedi anche

• HtmlTextWriter
• Html32TextWriter
• HttpBrowserCapabilities
• CreateHtmlTextWriterFromType(TextWriter, Type)
• ControlAdapter