Question

I do not understand why i did not get the help message after pressing the F1 key. When on windows form i got for instance one button and it has the focus the message is displayed as expected (after pressing F1) but when i got an empty form this is not happening. I suppose that an empty form will have by default focus set on it. ( i read that this event will be raised after pressing F1 for the control which got the focus)

Is this the right behavior, or i am missing something about the “HelpRequested” event on an empty form ? Is this the right way to raise the event based on focus or it could be configured to be raised also on another event (something like onMouseOver) ? May i create my own event and raise it ? (i do not want to add a special button only for help, for example press this button and display the help, help should be displayed only after F1 was pressed).

This is the code:

        private void Form1_Load(object sender, EventArgs e)
        {
           Form1.ActiveForm.HelpRequested += new HelpEventHandler(helpReq);

           //button1.HelpRequested += new HelpEventHandler(helpReq);
        }

        private void helpReq(object sender, HelpEventArgs hlpevent)
        {
          MessageBox.Show(((Control)sender).Text);
        }

Answer 1

• using Form1.ActiveForm, is not recommended. Change it to this
• there is no Text property associated with Control. Do you mean Tag?
• after performing the help event, you should set the HelpEventArgs.Handled to true
• instead of using events, you can just override OnHelpRequested in your form.

I would do someething like this:

 protected override void OnHelpRequested(object sender, HelpEventArgs e)
 {
    MessageBox.Show((Control) sender).Tag);
    e.Handled = true;

    base.OnHelpRequested(sender, e);
 }