/// <summary>
/// This helper method sends out all the strings in the queue by calling
/// the BytesSent callback again and again. It tries to send the string at the
/// front of queue. It contains a call to another helper method BytesSent
/// to ensure all the bytes from the front string are sent before calling this
/// method again to send the next string.
///
/// IMPLEMENTATION NOTE: Should be called from within a lock for thread-safety.
/// </summary>
private void HandleSendQueue()
{
while (sendQueue.Count > 0)
{
sendBytes = encoding.GetBytes(sendQueue.First <SendRequest>().Text);
try
{
socket.BeginSend(sendBytes, sendCount = 0, sendBytes.Length,
SocketFlags.None, new AsyncCallback(BytesSent), (object)null);
break;
}
catch (Exception ex)
{
SendRequest request = sendQueue.Dequeue();
ThreadPool.QueueUserWorkItem((WaitCallback)(x => request.SendBack(ex, request.Payload)));
}
}
}
/// <summary>
/// The callback method used when sending bytes. It makes sure that all of the bytes
/// are sent before making the approriate callback and call to HandleSendQueue.
///
/// IMPLEMENTATION NOTE: Should be called from within a lock for thread-safety.
/// </summary>
/// <param name="arg">Object containing status of asyn operation</param>
private void BytesSent(IAsyncResult arg)
{
try
{
sendCount = sendCount + socket.EndSend(arg);
}
catch (Exception ex)
{
SendRequest request = sendQueue.Dequeue();
ThreadPool.QueueUserWorkItem((WaitCallback)(x => request.SendBack(ex, request.Payload)));
HandleSendQueue();
return;
}
if (sendCount == sendBytes.Length)
{
lock (sendQueue)
{
SendRequest req = sendQueue.Dequeue();
ThreadPool.QueueUserWorkItem((WaitCallback)(x => req.SendBack((Exception)null, req.Payload)));
HandleSendQueue();
}
}
else
{
try
{
socket.BeginSend(sendBytes, sendCount, sendBytes.Length - sendCount,
SocketFlags.None, new AsyncCallback(BytesSent), (object)null);
}
catch (Exception ex)
{
SendRequest request = sendQueue.Dequeue();
ThreadPool.QueueUserWorkItem((WaitCallback)(x => request.SendBack(ex, request.Payload)));
HandleSendQueue();
}
}
}