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FtpWebRequest.EndGetRequestStream(IAsyncResult) Method

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Definition

Namespace:
System.Net
Assembly:
System.Net.Requests.dll
Assembly:
System.dll
Assembly:
netstandard.dll
Source:
FtpWebRequest.cs
Source:
FtpWebRequest.cs
Source:
FtpWebRequest.cs

Ends a pending asynchronous operation started with BeginGetRequestStream(AsyncCallback, Object).

public:
 override System::IO::Stream ^ EndGetRequestStream(IAsyncResult ^ asyncResult);
public override System.IO.Stream EndGetRequestStream (IAsyncResult asyncResult);
override this.EndGetRequestStream : IAsyncResult -> System.IO.Stream
Public Overrides Function EndGetRequestStream (asyncResult As IAsyncResult) As Stream

Parameters

asyncResult
IAsyncResult

The IAsyncResult object that was returned when the operation started.

Returns

Stream

A writable Stream instance associated with this instance.

Exceptions

ArgumentNullException

asyncResult is null.

ArgumentException

asyncResult was not obtained by calling BeginGetRequestStream(AsyncCallback, Object).

InvalidOperationException

This method was already called for the operation identified by asyncResult.

Examples

The following code example demonstrates ending an asynchronous operation to get a request's stream. This code example is part of a larger example provided for the FtpWebRequest class overview.

private:
   static void EndGetStreamCallback( IAsyncResult^ ar )
   {
      FtpState^ state = dynamic_cast<FtpState^>(ar->AsyncState);
      Stream^ requestStream = nullptr;

      // End the asynchronous call to get the request stream.
      try
      {
         requestStream = state->Request->EndGetRequestStream( ar );

         // Copy the file contents to the request stream.
         const int bufferLength = 2048;
         array<Byte>^buffer = gcnew array<Byte>(bufferLength);
         int count = 0;
         int readBytes = 0;
         FileStream^ stream = File::OpenRead( state->FileName );
         do
         {
            readBytes = stream->Read( buffer, 0, bufferLength );
            requestStream->Write( buffer, 0, bufferLength );
            count += readBytes;
         }
         while ( readBytes != 0 );
         Console::WriteLine( "Writing {0} bytes to the stream.", count );

         // IMPORTANT: Close the request stream before sending the request.
         requestStream->Close();

         // Asynchronously get the response to the upload request.
         state->Request->BeginGetResponse( gcnew AsyncCallback( EndGetResponseCallback ), state );
      }
      // Return exceptions to the main application thread.
      catch ( Exception^ e ) 
      {
         Console::WriteLine( "Could not get the request stream." );
         state->OperationException = e;
         state->OperationComplete->Set();
         return;
      }
   }

private static void EndGetStreamCallback(IAsyncResult ar)
{
    FtpState state = (FtpState) ar.AsyncState;

    Stream requestStream = null;
    // End the asynchronous call to get the request stream.
    try
    {
        requestStream = state.Request.EndGetRequestStream(ar);
        // Copy the file contents to the request stream.
        const int bufferLength = 2048;
        byte[] buffer = new byte[bufferLength];
        int count = 0;
        int readBytes = 0;
        FileStream stream = File.OpenRead(state.FileName);
        do
        {
            readBytes = stream.Read(buffer, 0, bufferLength);
            requestStream.Write(buffer, 0, readBytes);
            count += readBytes;
        }
        while (readBytes != 0);
        Console.WriteLine ("Writing {0} bytes to the stream.", count);
        // IMPORTANT: Close the request stream before sending the request.
        requestStream.Close();
        // Asynchronously get the response to the upload request.
        state.Request.BeginGetResponse(
            new AsyncCallback (EndGetResponseCallback),
            state
        );
    }
    // Return exceptions to the main application thread.
    catch (Exception e)
    {
        Console.WriteLine("Could not get the request stream.");
        state.OperationException = e;
        state.OperationComplete.Set();
        return;
    }
}

Remarks

If the operation has not completed, the EndGetRequestStream method blocks until the operation completes. To determine whether the operation has completed, check the IsCompleted property before calling EndGetRequestStream.

In addition to the exceptions noted in "Exceptions," EndGetRequestStream rethrows exceptions that were thrown while opening the stream for writing.

Note

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

Applies to

See also