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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
Actually I want to prevent opening form if its already opened. I can do
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


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

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

I hope this helps,


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
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
In addition to the other comments:

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

Hope this helps

"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
| how to do this in VB6 i.e. by setting cancel=true. Please tell me how can
| do this in VB.net I don't know how to use the eventArgs in VB.net and
| its help is available in MSDN.
| I'm thank full to you in advance.
Nov 21 '05 #13

This thread has been closed and replies have been disabled. Please start a new discussion.

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