void EndReceiveFromCallback(IAsyncResult iar)
{
SocketState state = iar.AsyncState as SocketState;
Socket socket = state.Socket;
try
{
int byteRead = socket.EndReceiveFrom(iar, ref state.RemoteEP);
MyCentorl.RecvMessage(state.Buffer);
}
catch (Exception e)
{
Console.WriteLine("发生异常！异常信息：");
Console.WriteLine(e.Message);
}
finally
{
//非常重要：继续异步接收
socket.BeginReceiveFrom(
state.Buffer, 0, state.Buffer.Length,
SocketFlags.None,
ref state.RemoteEP,
EndReceiveFromCallback,
state);
}
}
private void OnRecv(IAsyncResult ar)
{
try
{
int recvLength = socket.EndReceive(ar);
int pkgLength = 0;
byte[] data;
//如果半包数据不为空
if (null != backupBuffer)
{
//将半包和后面接收到的数据报拼接起来
data = backupBuffer.Concat(recvBuffer.Take(recvLength).ToArray()).ToArray();
}
else
{
data = recvBuffer.Take(recvLength).ToArray();
}
//解决连包问题
while (true)
{
// 1. recvEvent返回一个完整的数据包长度
pkgLength = MyCentorl.RecvMessage(data);
if (pkgLength <= 0 || pkgLength > maxPackage)
{
//出现异常，连接关闭
state = ServiceModel.BASESOCKET_STATE.SOCKET_ERROR;
Close();
break;
}
// 2. 如果正常处理完,则直接启动下次接收
if (pkgLength == data.Length)
{
////TraceUtil.Log("正常");
backupBuffer = null;
Array.Clear(recvBuffer, 0, recvBuffer.Length);
pkgLength = 0;
break;
}
// 3. 如果还未接收完,半包则在偏移处等待
else if (pkgLength > data.Length)
{
//将半包数据拷贝到backupBuffer
////TraceUtil.Log("半包");
backupBuffer = data.Take(data.Length).ToArray();
break;
}
// 4. 如果是连包，则循环处理
else if (pkgLength < data.Length)
{
//自增偏移量并跳过已经处理的包
////TraceUtil.Log("连包");
data = data.Skip(pkgLength).ToArray();
backupBuffer = null;
}
else
{
break;
}
}
StartRecv();
}
catch
{
state = ServiceModel.BASESOCKET_STATE.SOCKET_ERROR;
Close();
}
}