Message box with “Yes”, “No” choices in C#?

Question

I want to make a MessageBox confirmation. Here is the message box:

DialogResult dialog = MessageBox.Show("Etes vous sûre de vouloir fermer le programme ?", "Exit",MessageBoxButtons.YesNo);
if (dialog == DialogResult.Yes)
{
  Application.Exit();
}
else if (dialog == DialogResult.No)
{
    e.Cancel = true;
}

The problem is, when I click the YES Button, the popup does not close automatically. It will be closed after I click 2 times again. It should be closed from the first time.

It seems pretty easy but I'm not sure where is my mistake;

Answer 1

If it's in main form close method you can use it like this:

private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
    if (MessageBox.Show("Really close?", "Exit", MessageBoxButtons.YesNo) ==
        System.Windows.Forms.DialogResult.No)
        e.Cancel = true;
}

If user press "Yes" your form will be closed due to no close cancellation. If it is not main form close doesn't mean application exit. In this case you can close parent form explicitly after ShowDialog call.