How to keep parent form active while running process?

Question

Hello in my main form I am running a command-line exe to do some stuff for me. The only problem is as it is doing the stuff it needs to do my parent form is completely frozen until the process has ended.

Is there any way to run the process while keeping my parent form not frozen so buttons can be clicked, etc? Thank you, I have provided my code below for running the process.

        Process newprocess = new Process();
        ProcessStartInfo startInfo = new ProcessStartInfo();
        startInfo.CreateNoWindow = true;
        startInfo.UseShellExecute = false;
        startInfo.FileName = @"C:\tool.exe";
        startInfo.Arguments = "Some Arguments";
        newprocess.StartInfo = startInfo;
        newprocess.Start();

        newprocess.WaitForExit();

See: [Is there any async equivalent of Process.Start?](https://stackoverflow.com/questions/10788982/is-there-any-async-equivalent-of-process-start). Note: awaiting things un-freezes the UI. — Olivier Jacot-Descombes, Aug 12 '18 at 20:41
A `Process` can be event driven. You don't really need any `Task` to make it *async*. Different story if you need to process the results you receive from the program it runs, and that processing takes a long time. Then you'll need a `Task`. — Jimi, Aug 12 '18 at 21:55
Related: [process.WaitForExit() asynchronously](https://stackoverflow.com/questions/470256/process-waitforexit-asynchronously) — Theodor Zoulias, Sep 24 '20 at 07:43

score 1 · Accepted Answer · answered Aug 12 '18 at 21:32

1

Put the code in your question into a method, called say RunProcessAndWait(), and then in your event handler call Task.Run(() => RunProcessAndWait());

If you need to perform UI actions in the event, after the process has completed, use async:

private async void OnSomethingPressed(...) 
{
    await Task.Run(() => RunProcessAndWait());
    // Do UI (or other) things here
}

If you'd like to make the waiting more truly async - probably not necessary here, but for completeness, and it will save you one thread for a while - the SO question referred to in the comments has an answer showing how to do this.

answered Aug 12 '18 at 21:32

sellotape

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If possible, could I get an example of this code based on my code? I am just beginning learning c# and while that page is informative I don't know how to use my code with that code. Thank you – SockNastre Aug 12 '18 at 21:44
1

@smal: put the code from your question between `private void RunProcessAndWait() {` and `}`. And call the method shown here. – Olivier Jacot-Descombes Aug 12 '18 at 21:48
1

@smal Please note that `OnSomethingPressed` is an event handler (e.g., button click event) which you must _manually_ add the `async` keyword to it as shown in the answer. – 41686d6564 stands w. Palestine Aug 13 '18 at 01:21
Sorry for the late response, thank you guys so much it worked! :) – SockNastre Aug 17 '18 at 10:10

How to keep parent form active while running process?

1 Answers1