Winform app not closing

Question

I have a small app that a client uses to manually update some data. It is very basic; on load it populates a list of companies the user can select from and click a button to update the data in another system. The client wants to be able to run this same functionality from command line so I have added a background worker. When the app is launched, I check for a specific arg and if found I kick off the worker. Once the worker completes I call Close();

This all seems to work fine (the data gets updated as expected and the app appears to close), but when I check task manager the app is still running.

My questions:

1. What thing/things should I be looking for to find the cause of the app still running?
2. Is there a better way to do this?

Here's a sample of the code:

public MainForm()
        {
            InitializeComponent();

            var args = Environment.GetCommandLineArgs();
            Array.ForEach(args, x => x.ToLower());

           if (args.Contains("u"))
                backgroundWorker.RunWorkerAsync();

        }
 private void BackgroundWorkerDoWork(object sender, System.ComponentModel.DoWorkEventArgs e)
        {
           //call to web service to update data
        }

 private void BackgroundWorkerRunWorkerCompleted(object sender, System.ComponentModel.RunWorkerCompletedEventArgs e)
        {
           Close();
        }

Answer 1

Rather than calling Close(), try calling Application.Exit(). This will end the application rather than just closing the form.

Answer 2

2) Is there a better way to do this?

You could run the code from a Console App and be sure you have no WinForms/Threading problems.

As a variation on that, you can check the Commandline directly in Main() and not even execute the Application.Run(mainForm).

Answer 3

The backgroundworker is in another thread than the UI thread.

Create a delegate for handling stuff (stopping in this case) in the UI thread. Example here