HttpWebRequest::EndGetRequestStream Method (IAsyncResult^)

 
System_CAPS_noteNote

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Ends an asynchronous request for a Stream object to use to write data.

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

public:
virtual Stream^ EndGetRequestStream(
	IAsyncResult^ asyncResult
) override

Parameters

asyncResult
Type: System::IAsyncResult^

The pending request for a stream.

Return Value

Type: System.IO::Stream^

A Stream to use to write request data.

Exception Condition
ArgumentNullException

asyncResult is null.

IOException

The request did not complete, and no stream is available.

ArgumentException

asyncResult was not returned by the current instance from a call to BeginGetRequestStream.

InvalidOperationException

This method was called previously using asyncResult.

WebException

Abort was previously called.

-or-

An error occurred while processing the request.

The EndGetRequestStream method completes an asynchronous request for a stream that was started by the BeginGetRequestStream method. After the Stream object has been returned, you can send data with the HttpWebRequest by using the Stream::Write method.

System_CAPS_noteNote

You must set the value of the ContentLength property before writing data to the stream.

System_CAPS_cautionCaution

You must call the Stream::Close method to close the stream and release the connection for reuse. Failure to close the stream causes your application to run out of connections.

System_CAPS_noteNote

This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing in the .NET Framework.

The following code example uses the EndGetRequestStream method to end an asynchronous request for a stream instance.

#using <System.dll>

using namespace System;
using namespace System::Net;
using namespace System::IO;
using namespace System::Text;
using namespace System::Threading;
ref class HttpWebRequestBeginGetRequest
{
public:
   static ManualResetEvent^ allDone = gcnew ManualResetEvent( false );
   static void Main()
   {

      // Create a new HttpWebRequest object.
      HttpWebRequest^ request = dynamic_cast<HttpWebRequest^>(WebRequest::Create( "http://www.contoso.com/example.aspx" ));

      // Set the ContentType property.
      request->ContentType = "application/x-www-form-urlencoded";

      // Set the Method property to 'POST' to post data to the Uri.
      request->Method = "POST";

      // Start the asynchronous operation.    
      AsyncCallback^ del = gcnew AsyncCallback(GetRequestStreamCallback);
      request->BeginGetRequestStream( del, request );

      // Keep the main thread from continuing while the asynchronous
      // operation completes. A real world application
      // could do something useful such as updating its user interface. 
      allDone->WaitOne();
    }


private:
    static void GetRequestStreamCallback(IAsyncResult^ asynchronousResult)
    {
        HttpWebRequest^ request = dynamic_cast<HttpWebRequest^>(asynchronousResult->AsyncState);

        // End the operation
        Stream^ postStream = request->EndGetRequestStream(asynchronousResult);

        Console::WriteLine("Please enter the input data to be posted:");
        String^ postData = Console::ReadLine();

        // Convert the string into a byte array.
        array<Byte>^ByteArray = Encoding::UTF8->GetBytes(postData);

        // Write to the request stream.
        postStream->Write(ByteArray, 0, postData->Length);
        postStream->Close();

        // Start the asynchronous operation to get the response
        AsyncCallback^ del = gcnew AsyncCallback(GetResponseCallback);
        request->BeginGetResponse(del, request);
    }

   static void GetResponseCallback(IAsyncResult^ asynchronousResult)
   {
      HttpWebRequest^ request = dynamic_cast<HttpWebRequest^>(asynchronousResult->AsyncState);

      // End the operation
      HttpWebResponse^ response = dynamic_cast<HttpWebResponse^>(request->EndGetResponse(asynchronousResult));
      Stream^ streamResponse = response->GetResponseStream();
      StreamReader^ streamRead = gcnew StreamReader(streamResponse);
      String^ responseString = streamRead->ReadToEnd();
      Console::WriteLine(responseString);
      // Close the stream object
      streamResponse->Close();
      streamRead->Close();

      // Release the HttpWebResponse
      response->Close();
      allDone->Set();
   }
};

void main()
{
   HttpWebRequestBeginGetRequest::Main();
}

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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