C# RedirectStandardOutput输出与weaitforexit

Question

我有以下情况。我需要使用Process()在c#中运行一些bat文件，并且需要重定向它的输出，将结束错误输出到文件中。我知道如何做到这一点，如果我不为我的进程使用超时，我的代码就能正常工作。因此，程序可以一直工作到进程结束(我期望的是超时后被终止的进程)。下面是我的代码。

Process TcRunner = new Process();
TcRunner.StartInfo.FileName = "cmd.bat";
TcRunner.EnableRaisingEvents = true;
TcRunner.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
TcRunner.StartInfo.UseShellExecute = false;
TcRunner.StartInfo.RedirectStandardOutput = true;
TcRunner.StartInfo.RedirectStandardError = true;

try
{
     TcRunner.Start();
}
catch (Exception ex)
{
     Program.Print("Error: Could not start process\n");
     return 1;
}

string run_log_out = TcRunner.StandardOutput.ReadToEnd();
string run_log_err = TcRunner.StandardError.ReadToEnd();

if (!TcRunner.WaitForExit(5000)
{
    //kill the process
}

try
{
    StreamWriter run_out = new StreamWriter(@".\out");
    StreamWriter run_err = new StreamWriter(@".\err");
    run_out.WriteLine(run_log_out);
    run_err.WriteLine(run_log_err);
    run_out.Close();
    run_err.Close();
}
catch (Exception e)
{
    Console.WriteLine("Cannot open out/err for writing");
}

Answer 1

如果您想同时读取这两个流，则可能会出现死锁。因此，您应该尝试至少异步读取一个流。

在ProcessStartInfo.RedirectStandardOutput，的VisualStudio帮助中，我找到了以下信息：

   // Do not perform a synchronous read to the end of both
   // redirected streams.
   // string output = p.StandardOutput.ReadToEnd();
   // string error = p.StandardError.ReadToEnd();
   // p.WaitForExit();
   // Use asynchronous read operations on at least one of the streams.
   p.BeginOutputReadLine();
   string error = p.StandardError.ReadToEnd();
   p.WaitForExit();

这个link有一个很好的例子，他们通过将方法绑定到事件来异步读取两个流：

...
build.StartInfo.RedirectStandardOutput = true;
build.StartInfo.RedirectStandardError = true;
...
build.ErrorDataReceived += build_ErrorDataReceived;
build.OutputDataReceived += build_ErrorDataReceived;
...
build.BeginOutputReadLine();
build.BeginErrorReadLine();

static void build_ErrorDataReceived(object sender, DataReceivedEventArgs e)
{
    ...
}