如何为异步等待调用创建包装器？

据我所知，没有内置（或框架扩展）支持ConnectAsync/AcceptAsync/SendAsync/ReceiveAsync等等...我将如何编写自己的包装器，该包装器将受到异步等待机制的支持。例如，我当前的代码处理ReceiveAsync 内联和回调（在SocketAsyncEventArgs):

private void PostReceive(SocketAsyncEventArgs e)
{       
    e.SetBuffer(ReceiveBuffer.DataBuffer, ReceiveBuffer.Count, ReceiveBuffer.Remaining);            
    e.Completed += Receive_Completed;

            // if ReceiveAsync returns false, then completion happened inline
    if (m_RemoteSocket.ReceiveAsync(e) == false)
    {
        Receive_Completed(this, e);
    }                          
}

.

private void Receive_Completed(object sender, SocketAsyncEventArgs e)
{   
    e.Completed -= Receive_Completed;       

    if (e.BytesTransferred == 0 || e.SocketError != SocketError.Success)
    {
        if (e.BytesTransferred > 0)
        {                   
            OnDataReceived(e);
        }

        Disconnect(e);                
        return;
    }

    OnDataReceived(e);

    //
    // we do not push the SocketAsyncEventArgs back onto the pool, instead
    // we reuse it in the next receive call
    //
    PostReceive(e);
}

诀窍是使用任务完成源 http://msdn.microsoft.com/en-us/library/dd449174.aspx来处理这种情况。

我在博客上谈到了这一点。详细信息请参见为等待准备现有代码 http://reedcopsey.com/2010/12/14/c-5-async-part-3-preparing-existing-code-for-await/.