C# Windows Form formclosing error

Question

i am pretty newbie for coding. Here is i am having a problem:

private void pano_FormClosing(object sender, FormClosingEventArgs e)
    {
        DialogResult dialog = MessageBox.Show("Uygulamadan çıkış yapmak istediğinizden emin misiniz?", "Çıkış", MessageBoxButtons.YesNo);
        if (dialog == DialogResult.Yes)
        {
            Application.Exit();
        }
        else if (dialog == DialogResult.No)
        {
            e.Cancel = true;
        }

My purpose with this code block to ask user "are sure to quit" but unfortunetly when i close the application, i got notification window for 3 times? Is there any idea why thats happening or any solution?

Thanks a lot. Nuri.

Answer 1

Firstly, as Steve pointed out, remove the 'Yes' part - if not explicitly canceled, the event will close that form as a result of clicking.

Now, for the problem of yours. Seems like your alert is called twice. I was able to solve that easily by making a static bool close_alert_shown, and when the first alert is shown, set it to true so that the next alert won't pop up.

Final code looks like that:

            if (close_alert_shown) return;
            close_alert_shown = true;
            DialogResult dialog = MessageBox.Show("Uygulamadan çıkış yapmak istediğinizden emin misiniz?", "Çıkış", MessageBoxButtons.YesNo);
            if (dialog == DialogResult.No)
            {
                e.Cancel = true;
                close_alert_shown = false;
            }

And on the top of the form (before the public Form1() contructor line):

    static bool close_alert_shown = false;