Question

我正在监听我正在执行的控制台命令的输出：

Process p = new System.Diagnostics.Process();
ProcessStartInfo info = new System.Diagnostics.ProcessStartInfo();

info.FileName = "cmd.exe";
info.RedirectStandardInput = true;
info.RedirectStandardOutput = true;
info.RedirectStandardError = true;
info.UseShellExecute = false;
info.CreateNoWindow = true;

p.OutputDataReceived += new DataReceivedEventHandler(
    delegate (object sender, DataReceivedEventArgs e)
    {
        Console.WriteLine("Received data: " + e.Data);
        if (e.Data == "FAIL")
        {
            // I need to react to this outside the delegate,
            // e.g. stop the process and return <false>.
        }
    }

);

p.StartInfo = info;
p.Start();

using (StreamWriter sw = p.StandardInput)
{
    if (sw.BaseStream.CanWrite)
    {
        sw.WriteLine("echo Hello World 1");
        sw.WriteLine("echo FAIL");
        sw.WriteLine("echo Hello World 2");
        sw.WriteLine("echo Hello World 3");
        sw.WriteLine("exit");
    }
}

p.BeginOutputReadLine();
p.WaitForExit();

这可以按预期工作，但这里是我不知道该怎么做：当进程在其输出中生成“FAIL”行时，我想对委托之外的这个做出反应，即在方法中催生了这个过程。我怎样才能做到这一点？在我看来，我在委托中唯一的上下文是发送者（这是过程）和产生的数据。

我试图让委托抛出异常并在p.Start()和所有其他代码周围的try-catch块中捕获它，但异常不会被捕获。

Answer 1

如果您尝试等待然后返回值，则不希望立即对FAIL行作出反应。你应该做的是让你的代表设置一个标志。然后，您可以在p.WaitForExit来电后检查该国旗，并返回相应的值：

var hasFailed = false;

// Set up process

p.OutputDataReceived += new DataReceivedEventHandler(
    delegate (object sender, DataReceivedEventArgs e)
    {
        if (e.Data == "FAIL") hasFailed = true;
    }
);

// Start Process

p.WaitForExit();

if(hasFailed)
{
    // Handle the fact that the process failed and return appropriately.
}

// Otherwise the process succeeded and we can return normally.

如何监听控制台命令的输出并在侦听器之外作出反应？

1 个答案: