Manipulate the received data in a high performance c# socket server before it get's echoed back.

ProcessReceive.cs

private void ProcessReceive(SocketAsyncEventArgs e)
{
    if (e.BytesTransferred > 0 && e.SocketError == SocketError.Success)
    {
        var token = (AsyncUserToken)e.UserToken;

        //echo the data received back to the client
        var data = System.Text.Encoding.UTF8.GetString(e.Buffer, e.Offset, e.BytesTransferred);
        data = string.Format("{0}: {1}", DateTime.Now, data.ToUpper());

        var buffer = System.Text.Encoding.UTF8.GetBytes(data);

        e.SetBuffer(buffer, 0, buffer.Length);

        if (!token.Socket.SendAsync(e))
        {
            ProcessSend(e);
        }
    }
    else
    {
        CloseClientSocket(e);
    }
}