How to disable screen closure via X at top

Question

So, I have a WPF/Blazor hybrid with a second window for information. If the second window is closed off with the X in the top corner, it leaves the program hanging in the background, which is not good for system resources. In order to ensure that the user closes the window with the home button, how do I disable use of the X in the top right without having to close the whole application as in the following code snippet?

 public partial class AboutWin : Window
    {
        public AboutWin()
        {
            InitializeComponent();
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            MainWindow mainWindow = new MainWindow();
            mainWindow.Show();
            this.Hide();
        }

        private void Window_Closed(object sender, EventArgs e)
        {
            Application.Current.Shutdown();
        }
    }

Answer 1

Hi @Nigel , Welcome to Microsoft Q&A.

Your idea is totally doable.

Just add it to the Closing event.

Then call the Hide() method to hide the currently closed window//whatever you want to do.

   public AboutWin()
    {
        InitializeComponent();
        Closing += AboutWin_Closing; // Attach event handler
    }

    private void AboutWin_Closing(object sender, System.ComponentModel.CancelEventArgs e)
    {
        e.Cancel = true; // Cancel the closing event
        Hide(); // Hide the window instead of closing it
    }

This method is fully applicable to Winfrom or Wpf.

If it does not work in WPF/Blazor, please comment bellow.

Best Regards,

Jiale

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