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Cancelling event in event procedure

I want to cancel an event from its event procedure on some condition, I know
how to do this in VB6 i.e. by setting cancel=true. Please tell me how can I
do this in VB.net I don't know how to use the eventArgs in VB.net and neither
its help is available in MSDN.

I'm thank full to you in advance.
Nov 21 '05
12 18456
Adil,
Actually I want to prevent opening form if its already opened. I can do
this
by writing code at caller but I want some generic code that works for all
forms to prevent a form opening twice.


If you had written this direct than you had got this link and code direct

http://msdn.microsoft.com/library/de...posedtopic.asp

\\\
If Not TheSecondForm.I sDisposed then
dim TheSecondForm as SecondFormClass
TheSecondForm.S how
Else
TheSecondForm.S how
End if
////

This is a complex property normaly not showed or you have to change the
options.

I hope this helps,

Cor

Nov 21 '05 #11
We came across this same problem.

Our workround is to set a module level flag in the load event. Test for
this flag in the Actived event and close the form if the flag is set.
You can close a form from the activated event:

Public Class Form1
....
Private blnAbort as boolean

Private Sub Form1_Load(ByVa l sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load
If SomeCondition then
blnAbort=True
End If
End Sub

Private Sub Form1_Activated (ByVal sender As Object, ByVal e As
System.EventArg s) Handles MyBase.Activate d
If blnAbort then me.Close
End Sub
In message <C1************ *************** *******@microso ft.com>, Adil
Akram <Ad*******@disc ussions.microso ft.com> writes
I've already tried me.close but it comes up with following error

"Additional information: Cannot call Close() while doing CreateHandle(). "


--
Chris Petchey
Nov 21 '05 #12
Adil,
In addition to the other comments:

The "easiest" way to cancel a Form's Load event is to throw an exception.

Hope this helps
Jay

"Adil Akram" <Ad*******@disc ussions.microso ft.com> wrote in message
news:25******** *************** ***********@mic rosoft.com...
|I want to cancel an event from its event procedure on some condition, I
know
| how to do this in VB6 i.e. by setting cancel=true. Please tell me how can
I
| do this in VB.net I don't know how to use the eventArgs in VB.net and
neither
| its help is available in MSDN.
|
| I'm thank full to you in advance.
Nov 21 '05 #13

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