Re: Control Box Close Button Event - C# Discussion Boards

Martin#22-Jul-07 22:46

22-Jul-07 22:46

You are wellcome!

All the best,

Martin

VenkataRamana.Gali22-Jul-07 22:55

VenkataRamana.Gali

22-Jul-07 22:55

I am unable to add OnClosing Event.
Form is having only this.Closing event only

i.e., this.Closing += new System.ComponentModel.CancelEventHandler(From1_Closing);

plz tell me how to add OnClosing Event

regards
GV Ramana

Martin#22-Jul-07 23:01

22-Jul-07 23:01

OnClosing is th protected virtual method which fires the Closing event in the base Class (System.Windows.Forms.Form).
As you have your Form derived from Forms.Form, you don't have to handle the Event itselfe, you just can override the method.
Like I did!

All the best,

Martin

VenkataRamana.Gali22-Jul-07 23:15

VenkataRamana.Gali

22-Jul-07 23:15

got it. & another problem.

everytime getting DialogResult as Cancel if i click on X button also. how do i get this?

regards
GV Ramana

Martin#22-Jul-07 23:24

22-Jul-07 23:24

Hello,

Now you also want DialogResult.Cancel set, if the user closes with 'X'.
Just set it in the Closing or Closed event.

All the best,

Martin

Luc Pattyn23-Jul-07 2:17

23-Jul-07 2:17

Hi Martin,

I dont think it will work your way. Windows already sets DialogResult to Cancel on
hitting the Close box.

This is why: Microsoft intends the Close Button to be identical to a Cancel
action; closing the dialog or pressing Cancel button both indicate "hey, I dont want this,
I am not interested". It is part of the overall GUI conventions that MS came up with.

And, we have had a difference of opinion on this before: one should not go against
such conventions.

Smile | :)

Luc Pattyn

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Martin#23-Jul-07 2:41

23-Jul-07 2:41

Hello Luc,

Luc Pattyn wrote:
I dont think it will work your way

Luc Pattyn wrote:
Windows already sets DialogResult to Cancel on
hitting the Close box.

Have you tested it?
I did, with VS2003 .Net1.1!

Luc Pattyn wrote:
And, we have had a difference of opinion on this before: one should not go against
such conventions.

Really?
Help me with long-term memory, when was that.

All the best,

Martin

Luc Pattyn23-Jul-07 3:07

23-Jul-07 3:07

Martin# wrote:
Have you tested it?

Yes.

Martin# wrote:
Help me with long-term memory, when was that

IIRC it was about changing the behavior of a group of radio buttons; my point was and is
if it looks like standard controls, it should behave like them too.

Smile | :)

Luc Pattyn

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Martin#23-Jul-07 3:09

23-Jul-07 3:09

Luc Pattyn wrote:
Yes.

So why do we have different results than?

Luc Pattyn wrote:
IIRC it was about changing the behavior of a group of radio buttons;

Ahh, now I remember!

Luc Pattyn wrote:
my point was and is
if it looks like standard controls, it should behave like them too.

That's also what I think, but I think the point was to modify the behavior in combination with the style.

All the best,

Martin

Luc Pattyn23-Jul-07 3:30

23-Jul-07 3:30

Martin# wrote:
So why do we have different results than?

I see three possibilities:
- we have different systems
- there is a misunderstanding somewhere
- one of us is wrong (but who then?)

The last post from the OP seems to hint towards the third possibility, doesnt it ?
Smile | :)

Luc Pattyn

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Martin#23-Jul-07 3:43

23-Jul-07 3:43

Luc Pattyn wrote:
we have different systems

XP; VS2003; .Net1.1

Luc Pattyn wrote:
there is a misunderstanding somewhere

If I test following code at my Form, it does what I wrote in the comments of the code:

private void CancelButton_Click(object sender, System.EventArgs e)
{
    this.DialogResult = DialogResult.Cancel;
    this.Close();
}

protected override void OnClosing(CancelEventArgs e)
{
    if(this.DialogResult == DialogResult.None)
    {
        //'X' was pressed
    }
    else if(this.DialogResult == DialogResult.Cancel)
    {
        //CancelButton was Pressed
    }

    base.OnClosing (e);
}

Luc Pattyn wrote:
one of us is wrong (but who then?)

It's maybe a lack of self confidence, but I would assume it's me who missed something!

Luc Pattyn wrote:
The last post from the OP seems to hint towards the third possibility, doesnt it ?

I haven't understood this one!

Smile | :)

All the best,

Martin

Luc Pattyn23-Jul-07 4:02

23-Jul-07 4:02

Hi Martin,

the OP posted: "everytime getting DialogResult as Cancel if i click on X button also"
hence he gets DialogResult.Cancel both for the Cancel button and for the Close Box,
so that does not help him.

Maybe/probably the "Close Box implies Cancel result" only applies to dialogs (forms shown with
ShowDialog) where it matters most, and not to regular forms, shown with Show() ?
If so, you probably did the wrong experiment...

Smile | :)

Luc Pattyn

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catch { [Google] }

Martin#23-Jul-07 4:13

23-Jul-07 4:13

Luc Pattyn wrote:
Maybe/probably the "Close Box implies Cancel result" only applies to dialogs (forms shown with
ShowDialog) where it matters most, and not to regular forms, shown with Show() ?

Bingo!
Just tested it!

Luc Pattyn wrote:
If so, you probably did the wrong experiment

Did I?
I think he was never speaking of ShowDialog!

But anyway, you found the problem!
Got my '5' for that!

Smile | :)

All the best,

Martin

Luc Pattyn23-Jul-07 4:13

23-Jul-07 4:13

Furthermore, MSDN on Form.DialogResult says:
"clicking the Close button (the button with an X in the top-right corner of the form) causes the form to be hidden and the DialogResult property to be set to DialogResult.Cancel."

It does not say explicitly WHEN it does that, so I guess it is in base.OnClosing (e);

It does say "You can override the value assigned to the DialogResult property when the user clicks the Close button by setting the DialogResult property in an event handler for the Closing event of the form"

So I guess the base.OnClosing() does something like
if (DialogResult==None) DialogResult=Cancel

and hence your tip does not work, whereas setting it to something else
such as DialogResult=Yes; would work

(but it would then violate the GUI conventions, as I keep telling you).

Smile | :)

Luc Pattyn

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Martin#23-Jul-07 4:20

23-Jul-07 4:20

Luc Pattyn wrote:
and hence your tip does not work, whereas setting it to something else
such as DialogResult=Yes; would work

(but it would then violate the GUI conventions, as I keep telling you).

As it is only the case with ShowDialog and not with Show() and I tested it with show, I think it's not my fault.
I wouldn't have given such a suggestion if I knew that fact!

All the best,

Martin

Luc Pattyn23-Jul-07 4:41

23-Jul-07 4:41

And that's how we keep learning things every day.

"I think it's not my fault" Right, we all have a partial view on the whole thing,
every statement needs a lot of ifs and whens.

And the next question probably will be: when I hit the escape key, I want my form/dialog to
close, and I want to discriminate all three (ESC/CancelButton/CloseBox) ??? Big Grin | :-D

Luc Pattyn

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Martin#23-Jul-07 4:45

23-Jul-07 4:45

But only on Mondays!

Wait I think there is such a system allready on the market. YEP: "SAP" Laugh | :laugh:

All the best,

Martin

Luc Pattyn23-Jul-07 4:59