Wait until a process ends

Use Process.WaitForExit? Or subscribe to the Process.Exited event if you don't want to block? If that doesn't do what you want, please give us more information about your requirements.

I think you just want this:

var process = Process.Start(...);
process.WaitForExit();

See the MSDN page for the method. It also has an overload where you can specify the timeout, so you're not potentially waiting forever.

I do the following in my application:

Process process = new Process();
process.StartInfo.FileName = executable;
process.StartInfo.Arguments = arguments;
process.StartInfo.ErrorDialog = true;
process.StartInfo.WindowStyle = ProcessWindowStyle.Minimized;
process.Start();
process.WaitForExit(1000 * 60 * 5);    // Wait up to five minutes.

There are a few extra features in there which you might find useful...

You could use wait for exit or you can catch the HasExited property and update your UI to keep the user "informed" (expectation management):

System.Diagnostics.Process process = System.Diagnostics.Process.Start("cmd.exe");
while (!process.HasExited)
{
    //update UI
}
//done