Showing output of a running cmd process

Question

I have a C# code that uses command prompt to call a python script. The script currently takes about 25 seconds to run. When run in command prompt, the python script has several outputs until finally outputting "done". My C# code runs the script, but never closes the command prompt if I use "WaitForExit". So my thought is I need some kind of logic to check to see if "done" has been outputted, but the internet has not been very helpful with methodology.

Here's what I have, it currently only outputs the first line, "Microsoft Windows [Version 6.1.7601]". Obviously, no good.

var p = new Process();
p.StartInfo.FileName = "cmd.exe";
p.StartInfo.WorkingDirectory = @"C:\Optimization";
p.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardInput = true;


p.Start();


p.StandardInput.WriteLine(@"ipy spot_for_labview.py");

    StreamReader mySR = p.StandardOutput;
    string mystr = mySR.ReadLine();
    Debug.WriteLine(mystr);



p.WaitForExit(25000);  //25000 is a placeholder until better method found.

p.Close();

If there's anyway to close the process after it finishes, or to get all the cmd output I'm all ears.

Any help is appreciated.

Your first suggestion does not seem to output anything. I don't see how this could work without some kind of event structure or loop, when it first hits the "Debug.WriteLine" line, the output I need will not have happened yet. If I use p.BeginOutputReadLine(), what other method do I need to use to capture the output? I can't use p.StandardOutput, apparently that is sync. — Kyle Wright, Apr 15 '13 at 19:30
this So link may help !!! - http://stackoverflow.com/questions/206323/how-to-execute-command-line-in-c-get-std-out-results — aked, Apr 15 '13 at 19:31
It appears that process.BeginOutputReadLine() is all that's needed and that makes everything visible? Doesn't work in my case. — Kyle Wright, Apr 15 '13 at 19:48

score 1 · Answer 1 · answered Apr 15 '13 at 19:13

1

did you try this event ? Process.OutputDataReceived Event

or Process.ErrorDataReceived Event

here is the code from MSDN

    Process sortProcess;
    sortProcess = new Process();
    sortProcess.StartInfo.FileName = "Sort.exe";
    sortProcess.OutputDataReceived += new DataReceivedEventHandler(SortOutputHandler);

... .... ...

private static void SortOutputHandler(object sendingProcess, 
            DataReceivedEventArgs outLine)
        {
}

answered Apr 15 '13 at 19:13

aked

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Yes, I was unable to get that to work. It would output everything but not until I closed the command prompt manually. – Kyle Wright Apr 15 '13 at 19:18
Essentially. No -Q though. I'm not sure what the -Q would do...? – Kyle Wright Apr 15 '13 at 19:33
ProcessEXE.StartInfo.Arguments = Parameters; ? are you using this – aked Apr 15 '13 at 19:41
No, is that necessary? I am just including everything on the StandardInput.WriteLine line. – Kyle Wright Apr 15 '13 at 19:57

Showing output of a running cmd process

1 Answers1