public override IAsyncResult BeginWrite(byte[] buffer, int offset, int size, AsyncCallback cb, object state)
{
if (request.Aborted)
{
throw new WebException("The request was canceled.", null, WebExceptionStatus.RequestCanceled);
}
if (disposed)
{
throw new WebException("stream is closed", WebExceptionStatus.ConnectionClosed);
}
if (isRead)
{
throw new NotSupportedException("this stream does not allow writing");
}
if (buffer == null)
{
throw new ArgumentNullException("buffer");
}
int length = buffer.Length;
if (offset < 0 || length < offset)
{
throw new ArgumentOutOfRangeException("offset");
}
if (size < 0 || (length - offset) < size)
{
throw new ArgumentOutOfRangeException("size");
}
if (sendChunked)
{
lock (locker)
{
pendingWrites++;
pending.Reset();
}
}
WebAsyncResult result = new WebAsyncResult(cb, state);
AsyncCallback callback = new AsyncCallback(WriteAsyncCB);
if (sendChunked)
{
requestWritten = true;
string cSize = String.Format("{0:X}\r\n", size);
byte[] head = Encoding.ASCII.GetBytes(cSize);
int chunkSize = 2 + size + head.Length;
byte[] newBuffer = new byte[chunkSize];
Buffer.BlockCopy(head, 0, newBuffer, 0, head.Length);
Buffer.BlockCopy(buffer, offset, newBuffer, head.Length, size);
Buffer.BlockCopy(crlf, 0, newBuffer, head.Length + size, crlf.Length);
if (allowBuffering)
{
if (writeBuffer == null)
{
writeBuffer = new MemoryStream();
}
writeBuffer.Write(buffer, offset, size);
totalWritten += size;
}
buffer = newBuffer;
offset = 0;
size = chunkSize;
}
else
{
CheckWriteOverflow(request.ContentLength, totalWritten, size);
if (allowBuffering)
{
if (writeBuffer == null)
{
writeBuffer = new MemoryStream();
}
writeBuffer.Write(buffer, offset, size);
totalWritten += size;
if (request.ContentLength <= 0 || totalWritten < request.ContentLength)
{
result.SetCompleted(true, 0);
result.DoCallback();
return(result);
}
result.AsyncWriteAll = true;
requestWritten = true;
buffer = writeBuffer.GetBuffer();
offset = 0;
size = (int)totalWritten;
}
}
try
{
result.InnerAsyncResult = cnc.BeginWrite(request, buffer, offset, size, callback, result);
if (result.InnerAsyncResult == null)
{
if (!result.IsCompleted)
{
result.SetCompleted(true, 0);
}
result.DoCallback();
}
}
catch (Exception)
{
if (!IgnoreIOErrors)
{
throw;
}
result.SetCompleted(true, 0);
result.DoCallback();
}
totalWritten += size;
return(result);
}
