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c#processxnalauncherchild-process

Wait for all child processes of a ran process to finish C#


I'm developing a Launcher application for games. Much like XBOX Dashboard in XNA. I want to open back my program when the process which it started(the game) exits. With a simple game this is working:

[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool SetForegroundWindow(IntPtr hWnd);

[DllImportAttribute("User32.DLL")]
private static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
private const int SW_SHOW = 5;
private const int SW_MINIMIZE = 6;
private const int SW_RESTORE = 9;

public void Run(file)
{
    ProcessStartInfo startInfo = new ProcessStartInfo(file);
    Environment.CurrentDirectory = Path.GetDirectoryName(file);
    startInfo.Verb = "runas";
    var process = Process.Start(startInfo);
    process.WaitForExit();
    ShowWindow(Game1.Handle, SW_RESTORE);
    SetForegroundWindow(Game1.Handle);
}

The Game1.Handle is got from:

Handle = Window.Handle;

In the Game1's Load Content method.

My question is how I can make the window open up after all the child process that the ran process has started is finished?

Like a launcher launches a game.

I think some more advanced programmer may know the trick.

Thanks in advance!


Solution

  • You could use Process.Exited event

     int counter == 0;
         .....
    
         //start process, assume this code will be called several times
         counter++;
         var process = new Process ();
         process.StartInfo = new ProcessStartInfo(file);
    
         //Here are 2 lines that you need
         process.EnableRaisingEvents = true;
         //Just used LINQ for short, usually would use method as event handler
         process.Exited += (s, a) => 
        { 
          counter--;
          if (counter == 0)//All processed has exited
             {
             ShowWindow(Game1.Handle, SW_RESTORE);
            SetForegroundWindow(Game1.Handle);
             }
        }
        process.Start();
    

    More appropriate way for the game is to use named semaphore, but I would suggest you to start with Exited event, and then when you understand how it works, move to semaphore