Hide Command Window in C# Application

Question

Before you say its a duplicate question, please let me explain (as I've read all similar threads).

My application has both of these settings:

  procStartInfo.CreateNoWindow = true;
  procStartInfo.WindowStyle = ProcessWindowStyle.Hidden;

and is also has WindowsApplication as the output type.

The black window STILL comes up when I call a command line command. Is there anything else I can do to hide the window? It doesn't happen for all commands, XCOPY is a situation where it the black window does flash up. This only happens though when the destination I'm XCOPYing too already contains the file and it's prompting me if I want to replace it. Even if I pass in /Y it will still flash briefly.

I'm open to using vbscript if that will help, but any other ideas?

The client will call my executable and then pass in a command line command ie:

C:\MyProgram.exe start XCOPY c:\Test.txt c:\ProgramFiles\

Here's the full code of the application:

class Program
{
    static void Main(string[] args)
    {      
            string command = GetCommandLineArugments(args);

            // /c tells cmd that we want it to execute the command that follows and then exit.
            System.Diagnostics.ProcessStartInfo procStartInfo = new System.Diagnostics.ProcessStartInfo("cmd.exe", "/c " + command);

            procStartInfo.RedirectStandardOutput = true;
            procStartInfo.UseShellExecute = false;

            // Do not create the black window.
            procStartInfo.CreateNoWindow = true;
            procStartInfo.WindowStyle = ProcessWindowStyle.Hidden;

            System.Diagnostics.Process process = new System.Diagnostics.Process();
            process.StartInfo = procStartInfo;
            process.Start();

        }

    private static string GetCommandLineArugments(string[] args)
    {
        string retVal = string.Empty;

        foreach (string arg in args)
            retVal += " " + arg;


        return retVal;
    }
}

Answer 1

The problem is that you're using cmd.exe. Only its console window will be hidden, not the console window for the process you ask it to start. There's little point in using cmd.exe, unless you are trying to execute some of the commands it implements itself. Like COPY.

You can still suppress the window if you need cmd.exe, you'll have to use the /B option for Start. Type start /? at the command prompt to see options. Not that it helps, you can't use START COPY.

There's a specific quirk in xcopy.exe that might throw you off as well. It does not execute if you don't also redirect the input. It just fails to run without diagnostic.

Answer 2

i see that you are calling cmd and then passing the command as parameters. Instead call the command directly

e.g.

    System.Diagnostics.ProcessStartInfo procStartInfo = new System.DiagnosticsProcessStartInfo("xcopy", "<sourcedir> <destdir> <other parameters>");

procStartInfo.WindowStyle = ProcessWindowStyle.Hidden;

Answer 3

You can try adding

process.StartInfo.UseShellExecute = false; 

to your process

Answer 4

I had a similar task - It is possible to hide the window after creation via an API call. (In your case you maybe need a helper thread.)

[DllImport("user32.dll")]
static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);

If you know the handle of the new Window you can call

ShowWindow(hWnd, 0);

0 hides the window, 1 shows the window

To get the handle of the Window take a look at:

pinvoke.net enumwindows(user32)