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HttpWebRequest.HaveResponse Property

Definition

Gets a value that indicates whether a response has been received from an Internet resource.

public:
 virtual property bool HaveResponse { bool get(); };
public:
 property bool HaveResponse { bool get(); };
public virtual bool HaveResponse { get; }
public bool HaveResponse { get; }
member this.HaveResponse : bool
Public Overridable ReadOnly Property HaveResponse As Boolean
Public ReadOnly Property HaveResponse As Boolean

Property Value

true if a response has been received; otherwise, false.

Examples

The following code example checks the HaveResponse property to determine if a response has been received from an Internet resource.

      // Create a new 'HttpWebRequest' Object.
      HttpWebRequest^ myHttpWebRequest = dynamic_cast<HttpWebRequest^>(WebRequest::Create( "http://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("http://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.
Dim myHttpWebRequest As HttpWebRequest = CType(WebRequest.Create("http://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

Applies to