Redirect process output C#

Question

I would like to redirect the Process's standard output to a string for later parsing. I would also like to see the output on the screen, while the process is running, and not only when it finishes it's run.

Is that even possible?

Hinduism

Please provide more detail on what actually you are trying to do – Henrion

possible duplicate of C# get process output while running – Westmorland

I think the following are also relevant. c# - ProcessStartInfo hanging on "WaitForExit"? Why? - c# - Best way to interact with Command Line application - C# : Redirect console application output : How to flush the output? – Unclose

But wait, there are more: redirect - C# - Realtime console output redirection - c# - How can I redirect process output (console) to richtextbox? - c# - StandardOutput.ReadToEnd() hangs – Unclose

Answer 1

Use RedirectStandardOutput.

Sample from MSDN:

// Start the child process.
Process p = new Process();
// Redirect the output stream of the child process.
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "Write500Lines.exe";
p.Start();
// Do not wait for the child process to exit before
// reading to the end of its redirected stream.
// p.WaitForExit();
// Read the output stream first and then wait.
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();

Also see OutputDataReceived and BeginOutputReadLine() for an alternative to ReadToEnd(), that will better fulfill your "see output while the process is running" requirement.

Greensickness

Answer 2

If you want to execute an exe from your c# application and get the output from it then you can use the below code

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

p.StartInfo.FileName = "PATH TO YOUR FILE";
p.StartInfo.UseShellExecute = false;
p.StartInfo.Arguments = metalType + " " + graphHeight + " " + graphWidth;
p.StartInfo.CreateNoWindow = true;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.RedirectStandardError = true;              

p.EnableRaisingEvents = true;
p.Start();            
svgText = p.StandardOutput.ReadToEnd();

using(StreamReader s = p.StandardError)
{
    string error = s.ReadToEnd();
    p.WaitForExit(20000);
}

Don't forgete to write p.EnableRaisingEvents = true;

Henrion

EnableRaisingEvents is only needed for the Process.Exited event. – Cepheus