Hi Jim,
Just as our MVP and other community users said, you will fire the
event twice.
The event in .NET Framework is implemented by the MultiDelegate class,
which uses an linked list to save event handlers.It is not like an
Collection and won't check for duplicate handlers. for more information
,please refer to
ms-help://MS.MSDNQTR.2003FEB.1033/cpref/html/frlrfsystemmulticastdelegatecla
sstopic.htm
If you have any further questions , please be free to let me know!
Thanks!
Kind regards,
Ying-Shen Yu [MS]
Microsoft Support Engineer
This posting is provided "AS IS" with no warranties, and confers no rights.
You assume all risk for your use. 2001 Microsoft Corporation. All rights
reserved.
--------------------
| Content-Class: urn:content-classes:message
| From: "Jim" <
[email protected]>
| Sender: "Jim" <
[email protected]>
| References: <
[email protected]>
<
[email protected]>
| Subject: Re: Addhandler/Removehandler
| Date: Tue, 9 Sep 2003 14:47:50 -0700
| Lines: 42
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| Hi guys,
| Thanks for the replies. Yes that was my question really,
| whether anyone knew for sure that the handlers would in
| fact be duplicated or whether the event queue would
| detect that a hander was already registered for contol X
| and method Y. The documentation is not detailed enough
| to make that determination so I guess I just have to play
| with the code to see for sure.
| jim
| >-----Original Message-----
| >Hello,
| >
| >> We have developed some forms that dynamically build the
| >> controls and then need to add event handlers to them.
| >> Does anyone know the cumulative effect of adding
| handlers
| >> and not removing them? I have done Removehandler calls
| >> when the handler doesn't exist so I assume that the
| >> handlers are not maintained as a collection.
| >
| >Handlers may fire twice. I suggest you read the chapter
| about events in
| >the documentation:
| >
| >Events and Delegates (Visual Basic Language Concepts)
| >
http://msdn.microsoft.com/library/en-
| us/vbcn7/html/vaconeventsdelegatesinheritance.asp
| >
| >--
| >Herfried K. Wagner
| >MVP · VB Classic, VB.NET
| >
http://www.mvps.org/dotnet
| >
| >
| >.
| >
|
