Question

我有一个线程，检查用户是否在线

var user = (User)userObj;
if (!IsUserOnline(user)) return;
if (!TryToConnect(user)) return;
var TCP = user.CmdTCP;
Stream stm = TCP.GetStream();

每次都成功完成，但正如我

stm.Write(GetBytes("chk"), 0, 3);

然后

var bb = new byte[1];
try {
stm.Read(bb, 0, 1);
} catch (Exception e) { /*error*/ }
if (bb[0] == CHR_SUCCESS) {
//etc etc
}

如果用户第二次在线，则在读取时没有警告的流读取失败。没有例外，代码不会更进一步。线程停止，程序正常工作。

整线：

        var user = (User)userObj;
        if (!IsUserOnline(user)) return;
        if (!TryToConnect(user)) return;
        var TCP = user.CmdTCP;
        Stream stm = TCP.GetStream();
        try {
            stm.Write(GB("chk"), 0, 3);
            toLog("refresh::chk sent ;)");
        } catch (Exception e) {
            #region unable to send packet, online
            toLog("\trefresh::" + user.name + " is online (Connected, unable to send packet) " + e.Message);
            setUserStatus(user, userStatus.Online);
            return;
            #endregion
        }
        var bb = new byte[1];
        try {
            stm.Read(bb, 0, 1); //<<<<<<<<< here thread just ends, no toLog("..");, no exception
            toLog("refresh::got " + (char)bb[0]);
        } catch (Exception e) {
            #region unable to get packet, online
            toLog("\trefresh::" + user.name + " is online (Connected, unable to get packet) " + e.Message);
            setUserStatus(user, userStatus.Online);
            return;
            #endregion
        }
        if (bb[0] == CHR_SUCCESS) {
            try {
                stm.Write(GB(toStr(CHR_SSUCCESS)), 0, 1);
                toLog("refresh::CHR_SSUCCESS sent ;)");
            } catch (Exception e) {
                #region unable to send packet 2, online
                toLog("\trefresh::" user.name + " is online (Connected, unable to send packet #2) " + e.Message);
                setUserStatus(user, userStatus.Online);
                return;
                #endregion
            }
            toLog("\trefresh::" + user.name + " is online");
            setUserStatus(user, userStatus.Online);
        } else {
            for (int x = 0; x < 5; x++) {
                toLog("\t\trefresh::got wrong answer");
                System.Media.SystemSounds.Beep.Play();
                Thread.Sleep(500);
            }
            setUserStatus(user, userStatus.Online);
        }

Answer 1

看起来像你的Read（）块，因为没有数据可供读取。点击此处了解更多信息：What are some reasons NetworkStream.Read would hang/block?

如果我是对的，原因是服务器不发送数据。尝试调试服务器，而不是客户端。

TcpClient Stream.Read意外结束线程

1 个答案: