How do I run Command line commands from code

Question

I need to do 2 things: run a batch file (works fine), and run a command (does not work). The method for the command throws the exception 'file not found'. If I open a cmd window, and type the command, it works perfectly.

  private static void Rescan()
    {
        //System.Diagnostics.ProcessStartInfo psi = new System.Diagnostics.ProcessStartInfo("DEVCON ReScan");
        //psi.RedirectStandardOutput = true;
        //psi.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
        //psi.UseShellExecute = false;
        //System.Diagnostics.Process proc = System.Diagnostics.Process.Start(psi);
        System.Diagnostics.Process proc = new System.Diagnostics.Process();
        proc.StartInfo.FileName = "DEVCON ReScan";
        proc.StartInfo.RedirectStandardError = true;
        proc.StartInfo.RedirectStandardOutput = true;
        proc.StartInfo.UseShellExecute = false;
        proc.Start();
        proc.WaitForExit();
        System.IO.StreamReader myOutput = proc.StandardOutput;
        proc.WaitForExit(4000);
        if (proc.HasExited)
        {
            string output = myOutput.ReadToEnd();
            FileIO.WriteLog(_writePath, output);
        }

    }

The commented code also throws the same exception.

Answer 1

DEVCON ReScan is really the name of the executable? I guess the executable is DEVCON, while ReScan is a parameter. This means you have to set StartInfo.FileName to "DEVCON" and StartInfo.Arguments to "ReScan".

Answer 2

Is the DEVCON application actually in the working directory ? Otherwise it won't work unless you specify the full path to it.

Furthermore you have to specify the extension, so I suppose you'd go for "Devcon.exe", and specify the parameters not in the filename but in the parameters :)

Answer 3

Try this:

        ProcessStartInfo psi = new ProcessStartInfo();            
        psi.FileName = Environment.GetEnvironmentVariable("comspec");
        psi.CreateNoWindow = true;
        psi.RedirectStandardError = true;
        psi.RedirectStandardInput = true;
        psi.RedirectStandardOutput = true;
        psi.UseShellExecute = false;

        Process p = Process.Start(psi);

        ConsoleColor fc = Console.ForegroundColor;

        StreamWriter sw = p.StandardInput;
        StreamReader sr = p.StandardOutput;

        char[] buffer = new char[1024];
        int l = 0;

        sw.Write("DEVCON ReScan");
        sw.Write(sw.NewLine);

        Console.Write(">> ");

        l = sr.Read(buffer, 0, buffer.Length);

        for (int n = 0; n < l; n++)
            Console.Write(buffer[n] + " ");

        p.Close();