HttpWebRequest.HaveResponse-Eigenschaft

Ruft einen Wert ab, der angibt, ob eine Antwort von einer Internetressource empfangen wurde.

Namespace: System.Net
Assembly: System (in system.dll)

Syntax

'Declaration
Public ReadOnly Property HaveResponse As Boolean
'Usage
Dim instance As HttpWebRequest
Dim value As Boolean

value = instance.HaveResponse

public bool HaveResponse { get; }

public:
property bool HaveResponse {
    bool get ();
}

/** @property */
public boolean get_HaveResponse ()

public function get HaveResponse () : boolean

Eigenschaftenwert

true, wenn eine Antwort empfangen wurde, andernfalls false.

Beispiel

Im folgenden Codebeispiel wird die HaveResponse-Eigenschaft überprüft, um zu bestimmen, ob eine Antwort einer Internetressource empfangen wurde.

' Create a new 'HttpWebRequest' Object.
Dim myHttpWebRequest As HttpWebRequest = CType(WebRequest.Create("https://www.contoso.com"), HttpWebRequest)
Dim myHttpWebResponse As HttpWebResponse
' Display the 'HaveResponse' property of the 'HttpWebRequest' object to the console.
Console.WriteLine(ControlChars.Cr + "The value of 'HaveResponse' property before a response object is obtained :{0}", myHttpWebRequest.HaveResponse)
' Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable.
myHttpWebResponse = CType(myHttpWebRequest.GetResponse(), HttpWebResponse)
If myHttpWebRequest.HaveResponse Then
    Dim streamResponse As Stream = myHttpWebResponse.GetResponseStream()
    Dim streamRead As New StreamReader(streamResponse)
    Dim readBuff(256) As [Char]
    Dim count As Integer = streamRead.Read(readBuff, 0, 256)
    Console.WriteLine(ControlChars.Cr + "The contents of Html Page are :  " + ControlChars.Cr)
    While count > 0
        Dim outputData As New [String](readBuff, 0, count)
        Console.Write(outputData)
        count = streamRead.Read(readBuff, 0, 256)
    End While
      '  Close the Stream object.
      streamResponse.Close()
      streamRead.Close()
      ' Release the HttpWebResponse Resource.
      myHttpWebResponse.Close()
    Console.WriteLine(ControlChars.Cr + "Press 'Enter' key to continue..........")
    Console.Read()

Else
    Console.WriteLine(ControlChars.Cr + "The response is not received ")
End If

// Create a new 'HttpWebRequest' Object.
HttpWebRequest myHttpWebRequest=(HttpWebRequest)WebRequest.Create("https://www.contoso.com");
HttpWebResponse myHttpWebResponse;
// Display the 'HaveResponse' property of the 'HttpWebRequest' object to the console.
Console.WriteLine("\nThe value of 'HaveResponse' property before a response object is obtained :{0}",myHttpWebRequest.HaveResponse);
// Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable.
myHttpWebResponse=(HttpWebResponse)myHttpWebRequest.GetResponse();
if (myHttpWebRequest.HaveResponse)
{
    Stream streamResponse=myHttpWebResponse.GetResponseStream();
    StreamReader streamRead = new StreamReader( streamResponse );
    Char[] readBuff = new Char[256];
    int count = streamRead.Read( readBuff, 0, 256 );
    Console.WriteLine("\nThe contents of Html Page are :  \n");    
    while (count > 0) 
    {
        String outputData = new String(readBuff, 0, count);
        Console.Write(outputData);
        count = streamRead.Read(readBuff, 0, 256);
    }
    // Close the Stream object.
    streamResponse.Close();
    streamRead.Close();
    // Release the HttpWebResponse Resource.
    myHttpWebResponse.Close();
    Console.WriteLine("\nPress 'Enter' key to continue..........");
    Console.Read();
}
else
{
    Console.WriteLine("\nThe response is not received ");
}

      // Create a new 'HttpWebRequest' Object.
      HttpWebRequest^ myHttpWebRequest = dynamic_cast<HttpWebRequest^>(WebRequest::Create( "https://www.contoso.com" ));
      HttpWebResponse^ myHttpWebResponse;
      
      // Display the 'HaveResponse' property of the 'HttpWebRequest' object to the console.
      Console::WriteLine( "\nThe value of 'HaveResponse' property before a response object is obtained : {0}", myHttpWebRequest->HaveResponse );
      
      // Assign the response object of 'HttpWebRequest' to a 'HttpWebResponse' variable.
      myHttpWebResponse = dynamic_cast<HttpWebResponse^>(myHttpWebRequest->GetResponse());
      if ( myHttpWebRequest->HaveResponse )
      {
         Stream^ streamResponse = myHttpWebResponse->GetResponseStream();
         StreamReader^ streamRead = gcnew StreamReader( streamResponse );
         array<Char>^readBuff = gcnew array<Char>(256);
         int count = streamRead->Read( readBuff, 0, 256 );
         Console::WriteLine( "\nThe contents of Html Page are :  \n" );
         while ( count > 0 )
         {
            String^ outputData = gcnew String( readBuff,0,count );
            Console::Write( outputData );
            count = streamRead->Read( readBuff, 0, 256 );
         }
         streamResponse->Close();
         streamRead->Close();
         
         // Release the HttpWebResponse Resource.
         myHttpWebResponse->Close();
         Console::WriteLine( "\nPress 'Enter' key to continue.........." );
         Console::Read();
      }
      else
      {
         Console::WriteLine( "\nThe response is not received " );
      }
   }
   catch ( WebException^ e ) 
   {
      Console::WriteLine( "\nWebException Caught" );
      Console::WriteLine( "\nSource  : {0}", e->Source );
      Console::WriteLine( "\nMessage : {0}", e->Message );
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "Exception Caught" );
      Console::WriteLine( "Source  : {0}", e->Source );
      Console::WriteLine( "Message : {0}", e->Message );
   }

}

// Create a new 'HttpWebRequest' Object.
HttpWebRequest myHttpWebRequest = (HttpWebRequest)
    (WebRequest.Create("https://www.contoso.com"));
HttpWebResponse myHttpWebResponse;
// Display the 'HaveResponse' property of the 'HttpWebRequest' 
// object to the console.
Console.WriteLine("\nThe value of 'HaveResponse' property before a"
    +" response object is obtained :{0}", 
    System.Convert.ToString(myHttpWebRequest.get_HaveResponse()));
// Assign the response object of 'HttpWebRequest' to a
//'HttpWebResponse' variable.
myHttpWebResponse = (HttpWebResponse)
    (myHttpWebRequest.GetResponse());

if (myHttpWebRequest.get_HaveResponse()) {
    Stream streamResponse = myHttpWebResponse.GetResponseStream();
    StreamReader streamRead = new StreamReader(streamResponse);
    char readBuff[] = new char[256];
    int count = streamRead.Read(readBuff, 0, 256);

    Console.WriteLine("\nThe contents of Html Page are :  \n");

    while (count > 0) {
        String outputData = new String(readBuff, 0, count);
        Console.Write(outputData);
        count = streamRead.Read(readBuff, 0, 256);
    }

    // Close the Stream object.
    streamResponse.Close();
    streamRead.Close();
    // Release the HttpWebResponse Resource.
    myHttpWebResponse.Close();
    Console.WriteLine("\nPress 'Enter' key to continue..........");
    Console.Read();
}
else {
    Console.WriteLine("\nThe response is not received ");
}

Plattformen

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

.NET Compact Framework

Unterstützt in: 2.0, 1.0

Siehe auch

Referenz

HttpWebRequest-Klasse
HttpWebRequest-Member
System.Net-Namespace