intercept form closing

  • Thread starter Thread starter Alexander Stetsenko
  • Start date Start date
A

Alexander Stetsenko

Hi.

What I need is to intercept MDI Parent form closing.

As for now, MDI Parent form closing event is rased only after all child
forms are closed.
And I can't cancel this operation. If user had accidentaly clicked form X
close button
I want to ask him if hi realy want to close thw application. BEFORE all
opened child windows
are closed.

How can I do this?

Thanks.
Alexander.
 
Hi,
You can give users the option to change their minds by handling the
FormClosing event and setting FormClosingEventArgs.Cancel to true or false as
appropriate:
//if we set e.cancel to true means it will not close the application
void Form1_FormClosing(object sender, FormClosingEventArgs e) {
if( e.CloseReason == CloseReason.UserClosing){
DialogResult result = MessageBox.Show(
"Abort your application?", "Application In Progress",
MessageBoxButtons.YesNo);
e.Cancel = (result == DialogResult.No);
}
}
 
It will work if FormClosing event fire before Closing (and before closing
all child windows)
But if is fired after Closing event. So it can't help me. All child windows
at that moment are closed :(

Other solutions?
 
What I need is to intercept MDI Parent form closing.

As for now, MDI Parent form closing event is rased only after all child
forms are closed.
And I can't cancel this operation. If user had accidentaly clicked form X
close button
I want to ask him if hi realy want to close thw application. BEFORE all
opened child windows
are closed.

How can I do this?
Click to expand...

It's been a long time since I've worked with MDI windows but what about
overriding the WndProc method and intercepting whatever message is posted
when the user clicks on the close button there?
 
It will work if FormClosing event fire before Closing (and before closing
all child windows)
But if is fired after Closing event. So it can't help me. All child windows
at that moment are closed :(

Other solutions?







- Show quoted text -
Click to expand...

try following code. It works for me. No matter whether how many child
windows are open. Trap FormClosing event and not FormClosed event. You
can put additional loginc in If to check if any child window is
visible ot not and if not then don't ask any question.

private void MDIParent1_FormClosing(object sender,
FormClosingEventArgs e)
{
if (MessageBox.Show("Close?",
AppDomain.CurrentDomain.ToString(), MessageBoxButtons.YesNo) ==
DialogResult.No)
{
e.Cancel = true;
}
}

This is definatly working for me as we had recently deliver one of our
project to client with simillar feature
 
Thanks all!

Your solutions works fine.

I found the problem. It is Janus MdiTab Manager. Without it the sequence of
events is correct and
FormClosing is works fine. But the I activate it all child forms closes
before I enter any of form closing event handlers.

Thanks again.
 
I found the problem. It is Janus MdiTab Manager. Without it the sequence
of events is correct and
FormClosing is works fine. But the I activate it all child forms closes
before I enter any of form closing event handlers.
Click to expand...

Is the Janus component part of the inheritance chain for your form? Or is
it simply adding an event handler to the FormClosing event? Either way,
it seems to me that this is an example of why it's a good idea to override
the OnFormClosing() method in your form, rather than to subscribe to its
own event. If you override the OnFormClosing() method, you can ensure
that your code is executed first, before any base class and before any
event handlers. You can even avoid calling any of that other code if you
don't need to (if canceling the close, for example).

Pete
 
It's a component, placed on form.
I've already tried to override OnFormClosing, but with no success.
It seems like this component handling Windows messages directly.
 
It's a component, placed on form.
I've already tried to override OnFormClosing, but with no success.
It seems like this component handling Windows messages directly.
Click to expand...

I don't see how it can do that, unless it's doing some low-level message
hooks or something. That's certainly not the sort of behavior I'd expect
from a .NET Forms component. Sounds like a good reason not to use that
component if it can be helped. :)

Pete
 
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