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WebRequest.EndGetResponse Method

When overridden in a descendant class, returns a WebResponse.

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

public virtual WebResponse EndGetResponse(
	IAsyncResult asyncResult
)

Parameters

asyncResult
Type: System.IAsyncResult

An IAsyncResult that references a pending request for a response.

Return Value

Type: System.Net.WebResponse
A WebResponse that contains a response to the Internet request.

ExceptionCondition
NotImplementedException

Any attempt is made to access the method, when the method is not overridden in a descendant class.

The EndGetResponse method completes an asynchronous request for an Internet resource that was started with the BeginGetResponse method.

NoteNote:

The WebRequest class is an abstract class. The actual behavior of WebRequest instances at run time is determined by the descendant class returned by the WebRequest.Create method. For more information about default values and exceptions, see the documentation for the descendant classes, such as HttpWebRequest and FileWebRequest.

The following example calls the EndGetResponse to retrieve the target resource.

using System;
using System.Net;
using System.IO;
using System.Text;
using System.Threading;



public class RequestState
{
  // This class stores the state of the request. 
  const int BUFFER_SIZE = 1024;
  public StringBuilder requestData;
  public byte[] bufferRead;
  public WebRequest request;
  public WebResponse response;
  public Stream responseStream;
  public RequestState()
  {
    bufferRead = new byte[BUFFER_SIZE];
    requestData = new StringBuilder("");
    request = null;
    responseStream = null;
  }
}
class WebRequest_BeginGetResponse
{
  public static ManualResetEvent allDone= new ManualResetEvent(false);
  const int BUFFER_SIZE = 1024;
  static void Main()
  {
    try
    {
      // Create a new webrequest to the mentioned URL.   
      WebRequest myWebRequest= WebRequest.Create("http://www.contoso.com");

      // Please, set the proxy to a correct value. 
      WebProxy proxy=new WebProxy("myproxy:80");

      proxy.Credentials=new NetworkCredential("srikun","simrin123");
      myWebRequest.Proxy=proxy;
      // Create a new instance of the RequestState.
      RequestState myRequestState = new RequestState();
      // The 'WebRequest' object is associated to the 'RequestState' object.
      myRequestState.request = myWebRequest;
      // Start the Asynchronous call for response.
      IAsyncResult asyncResult=(IAsyncResult) myWebRequest.BeginGetResponse(new AsyncCallback(RespCallback),myRequestState);
      allDone.WaitOne();
      // Release the WebResponse resource.
      myRequestState.response.Close();
      Console.Read();
    }
    catch(WebException e)
    {
      Console.WriteLine("WebException raised!");
      Console.WriteLine("\n{0}",e.Message);
      Console.WriteLine("\n{0}",e.Status);
    } 
    catch(Exception e)
    {
      Console.WriteLine("Exception raised!");
      Console.WriteLine("Source : " + e.Source);
      Console.WriteLine("Message : " + e.Message);
    }
  }
  private static void RespCallback(IAsyncResult asynchronousResult)
  {  
    try
    {
      // Set the State of request to asynchronous.
      RequestState myRequestState=(RequestState) asynchronousResult.AsyncState;
      WebRequest  myWebRequest1=myRequestState.request;
      // End the Asynchronous response.
      myRequestState.response =  myWebRequest1.EndGetResponse(asynchronousResult);
      // Read the response into a 'Stream' object.
      Stream responseStream = myRequestState.response.GetResponseStream();
      myRequestState.responseStream=responseStream;
      // Begin the reading of the contents of the HTML page and print it to the console.
      IAsyncResult asynchronousResultRead = responseStream.BeginRead(myRequestState.bufferRead, 0, BUFFER_SIZE, new AsyncCallback(ReadCallBack), myRequestState);

    }
    catch(WebException e)
    {
      Console.WriteLine("WebException raised!");
      Console.WriteLine("\n{0}",e.Message);
      Console.WriteLine("\n{0}",e.Status);
    } 
    catch(Exception e)
    {
      Console.WriteLine("Exception raised!");
      Console.WriteLine("Source : " + e.Source);
      Console.WriteLine("Message : " + e.Message);
    }
  }
  private static   void ReadCallBack(IAsyncResult asyncResult)
  {
    try
    {
      // Result state is set to AsyncState.
      RequestState myRequestState = (RequestState)asyncResult.AsyncState;
      Stream responseStream = myRequestState.responseStream;
      int read = responseStream.EndRead( asyncResult );
      // Read the contents of the HTML page and then print to the console. 
      if (read > 0)
      {
        myRequestState.requestData.Append(Encoding.ASCII.GetString(myRequestState.bufferRead, 0, read));
        IAsyncResult asynchronousResult = responseStream.BeginRead( myRequestState.bufferRead, 0, BUFFER_SIZE, new AsyncCallback(ReadCallBack), myRequestState);
      }
      else
      {
        Console.WriteLine("\nThe HTML page Contents are:  ");
        if(myRequestState.requestData.Length>1)
        {
          string sringContent;
          sringContent = myRequestState.requestData.ToString();
          Console.WriteLine(sringContent);
        }
        Console.WriteLine("\nPress 'Enter' key to continue........");
        responseStream.Close();
        allDone.Set();
      }
    }
    catch(WebException e)
    {
      Console.WriteLine("WebException raised!");
      Console.WriteLine("\n{0}",e.Message);
      Console.WriteLine("\n{0}",e.Status);
    } 
    catch(Exception e)
    {
      Console.WriteLine("Exception raised!");
      Console.WriteLine("Source : {0}" , e.Source);
      Console.WriteLine("Message : {0}" , e.Message);
    }

  }

}
#using <mscorlib.dll>
#using <System.dll>
using namespace System;
using namespace System::Net;
using namespace System::IO;
using namespace System::Text;
using namespace System::Threading;

public __gc class RequestState {
   // This class stores the state of the request.
   static const int BUFFER_SIZE = 1024;
public:
   StringBuilder*  requestData;
   Byte  bufferRead[];
   WebRequest*  request;
   WebResponse*  response;
   Stream*  responseStream;

   RequestState() {
      bufferRead = new Byte[BUFFER_SIZE];
      requestData = new StringBuilder(S"");
      request = 0;
      responseStream = 0;
   }
};

__gc class WebRequest_BeginGetResponse {
public:
   static ManualResetEvent* allDone = new ManualResetEvent(false);
   static const int BUFFER_SIZE = 1024;

   static void RespCallback(IAsyncResult* asynchronousResult) {
      try {
         // Set the State of request to asynchronous.
         RequestState* myRequestState=dynamic_cast<RequestState*> (asynchronousResult->AsyncState);
         WebRequest*  myWebRequest1=myRequestState->request;
         // End the Asynchronous response.
         myRequestState->response =  myWebRequest1->EndGetResponse(asynchronousResult);
         // Read the response into a 'Stream' object.
         Stream*  responseStream = myRequestState->response->GetResponseStream();
         myRequestState->responseStream=responseStream;
         // Begin the reading of the contents of the HTML page and print it to the console.
         IAsyncResult* asynchronousResultRead = responseStream->BeginRead(myRequestState->bufferRead, 0, BUFFER_SIZE, new AsyncCallback(0, ReadCallBack), myRequestState);

      } catch (WebException* e) {
         Console::WriteLine(S"WebException raised!");
         Console::WriteLine(S"\n {0}", e->Message);
         Console::WriteLine(S"\n {0}", __box(e->Status));
      } catch (Exception* e) {
         Console::WriteLine(S"Exception raised!");
         Console::WriteLine(S"Source : {0}", e->Source);
         Console::WriteLine(S"Message : {0}", e->Message);
      }
   }

   static  void ReadCallBack(IAsyncResult* asyncResult) {
      try {
         // Result state is set to AsyncState.
         RequestState* myRequestState = dynamic_cast<RequestState*>(asyncResult->AsyncState);
         Stream*  responseStream = myRequestState->responseStream;
         int read = responseStream->EndRead(asyncResult);
         // Read the contents of the HTML page and then print to the console.
         if (read > 0) {
            myRequestState->requestData->
               Append(Encoding::ASCII->GetString(myRequestState->bufferRead, 0, read));
            IAsyncResult* asynchronousResult =
               responseStream->BeginRead(myRequestState->bufferRead, 0, BUFFER_SIZE,
               new AsyncCallback(0, ReadCallBack), myRequestState);
         } else {
            Console::WriteLine(S"\nThe HTML page Contents are:  ");
            if (myRequestState->requestData->Length>1) {
               String* sringContent;
               sringContent = myRequestState->requestData->ToString();
               Console::WriteLine(sringContent);
            }
            Console::WriteLine(S"\nPress 'Enter' key to continue........");
            responseStream->Close();
            allDone->Set();
         }
      } catch (WebException* e) {
         Console::WriteLine(S"WebException raised!");
         Console::WriteLine(S"\n {0}", e->Message);
         Console::WriteLine(S"\n {0}", __box(e->Status));
      } catch (Exception* e) {
         Console::WriteLine(S"Exception raised!");
         Console::WriteLine(S"Source : {0}" , e->Source);
         Console::WriteLine(S"Message : {0}" , e->Message);
      }
   }
};

int main() {
   try {
      // Create a new webrequest to the mentioned URL.
      WebRequest* myWebRequest= WebRequest::Create(S"http://www.contoso.com");

      // Please, set the proxy to a correct value.
      WebProxy* proxy = new WebProxy(S"myproxy:80");
      proxy->Credentials = new NetworkCredential(S"srikun", S"simrin123");
      myWebRequest->Proxy=proxy;
      // Create a new instance of the RequestState.
      RequestState* myRequestState = new RequestState();
      // The 'WebRequest' object is associated to the 'RequestState' object.
      myRequestState->request = myWebRequest;
      // Start the Asynchronous call for response.
      IAsyncResult* asyncResult =
         dynamic_cast<IAsyncResult*> (myWebRequest->BeginGetResponse(new AsyncCallback(asyncResult, WebRequest_BeginGetResponse::RespCallback), myRequestState));
      WebRequest_BeginGetResponse::allDone->WaitOne();
      // Release the WebResponse resource.
      myRequestState->response->Close();
      Console::Read();
   } catch (WebException* e) {
      Console::WriteLine(S"WebException raised!");
      Console::WriteLine(S"\n {0}", e->Message);
      Console::WriteLine(S"\n {0}", __box(e->Status));
   } catch (Exception* e) {
      Console::WriteLine(S"Exception raised!");
      Console::WriteLine(S"Source : {0}", e->Source);
      Console::WriteLine(S"Message : {0}", e->Message);
   }
}

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

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