如下，是不是又会从receivecallback重新开始？

Question

private void recievecallback(IAsyncResult AR) //回发数据个客户端 { try { Socket Rsocket = (Socket)AR.AsyncState; int Rend = Rsocket.EndReceive(AR); for (int i = 0; i < clientnum; i++) { if (clientsocket[i].Connected) { clientsocket[i].Send(msgbuffer, 0, Rend, 0); } Rsocket.BeginReceive(msgbuffer, 0, msgbuffer.Length, 0, new AsyncCallback(recievecallback), Rsocket); } } catch { } } private void receivecallback(IAsyncResult AR) { try { int Rend = clientsocket.EndReceive(AR); listBox1.Items.Add(Encoding.Unicode.GetString(msgbuffer, 0, Rend)); clientsocket.BeginReceive(msgbuffer, 0, msgbuffer.Length, 0, new AsyncCallback(receivecallback), null); } catch { MessageBox.Show("已经与服务器断开!"); } } clientsocket.BeginReceive(msgbuffer, 0, msgbuffer.Length, 0, new AsyncCallback(receivecallback), null); 为什么又new AsyncCallback(receivecallback),这儿，然后是不是又从receivecallback重新开始？

Answer 1

因为这里必须是一个 AsyncCallback 委托，这个是BeginReceive的构造参数。
public IAsyncResult BeginReceive (
byte[] buffer,
int offset,
int size,
SocketFlags socketFlags,
AsyncCallback callback,
Object state
)
参数：
buffer
Byte 类型的数组，它是存储接收到的数据的位置。 
offset
buffer 参数中存储所接收数据的位置，该位置从零开始计数。 
size
要接收的字节数。 
socketFlags
SocketFlags 值的按位组合。 
callback
一个 AsyncCallback 委托，它引用操作完成时要调用的方法。 
state
一个用户定义对象，其中包含接收操作的相关信息。当操作完成时，此对象会被传递给 EndReceive 委托。

也就是new AsyncCallback（receivecallback）后又会执行receivecallback（）这个方法。