473,396 Members | 1,764 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,396 software developers and data experts.

Removing All Event Handlers

Hi,

Is there a way to remove all event handlers for a control's event? Say, i have a button and i want
to remove all button.Click events for it - i don't know how many of them was hooked to the event and
what are the functions hooked, but i need to make sure that i unwired all of them at once.

I could unwire event handlers if i knew the functions:

button.Click += new EventHandler(OnMyBtnClick); // Wire event handler
....
button.Click -= new EventHandler(OnMyBtnClick); // Unwire event handler

But again, i don't know which/how many event handlers are wired to the event.
Any ideas/comments would be highly appreciated!

Thank you
Andrey
Nov 17 '05 #1
1 55563
Directly no, in large part because you cannot simply set the event to null.

Indirectly, you could make the actual event private and create a property
around it that tracks all of the delegates being added/subtracted to it.

Take the following:

ArrayList delegates = new ArrayList();

private event EventHandler MyRealEvent;

public event EventHandler MyEvent
{
add
{
MyRealEvent += value;
delegates.Add(value);
}

remove
{
MyRealEvent -= value;
delegates.Remove(value);
}
}

public void RemoveAllEvents()
{
foreach(EventHandler eh in delegates)
{
MyRealEvent -= eh;
}
delegates.Clear();
}

In this code, we create a wrapper around MyRealEvent (which is what you
would actually trigger internally), so that anytime something is
added/subtracted to it, a list of those EventHandlers is updated accordingly.
When you finally need to clear out all of the events, simply call
RemoveAllEvents() (poorly named I know) which iterates through the list of
EventHandlers and removes each in turn from the real event.

Brendan
"MuZZy" wrote:
Hi,

Is there a way to remove all event handlers for a control's event? Say, i have a button and i want
to remove all button.Click events for it - i don't know how many of them was hooked to the event and
what are the functions hooked, but i need to make sure that i unwired all of them at once.

I could unwire event handlers if i knew the functions:

button.Click += new EventHandler(OnMyBtnClick); // Wire event handler
....
button.Click -= new EventHandler(OnMyBtnClick); // Unwire event handler

But again, i don't know which/how many event handlers are wired to the event.
Any ideas/comments would be highly appreciated!

Thank you
Andrey

Nov 17 '05 #2

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

Similar topics

5
by: Charles Law | last post by:
I think I asked the wrong question last time, so I am starting a separate post to distinguish them. Take five classes: ClassA and ClassW...Z ClassA raises five events: Event1...5 ClassW...Z...
13
by: Charles Law | last post by:
Mr "yEaH rIgHt" posted the following link about a week ago in answer to my question about removing event handlers. > http://www.vbinfozine.com/t_bindevt.shtml Following on from that post, the...
16
by: Hamed | last post by:
Hello I am developing a utility to be reused in other programs. It I have an object of type Control (a TextBox, ComboBox, etc.) that other programmers use it in applications. they may set some...
14
by: Hamed | last post by:
Hello It seems that I should implement ICloneable to implement my own clone object. the critical point for me is to make a control object based on another control object that all of its event...
0
by: KeironNicholson | last post by:
Hello, Does anybody know if there is ANY way to either get a reference to or just remove event handlers that you didn't declare yourself? (I am writing a plugin, but want to change the...
5
by: gnassar | last post by:
Essentially my problem is that .NET 2005 is removing my event handlers. There's no real special things about my project, it just continually removes them all. It starts on the open of a...
1
by: Armin Zingler | last post by:
Hi, I add event handlers to different events of objects of different type. In an array or arraylist, I want to store the information about which events I added. Later, I want to process the...
0
by: khalid galal | last post by:
Hi, i am having a problem with removing event handlers, it is when creating nested event handlers (an event handler raising another event handler) where a part of the code is private void...
5
by: Lloyd Sheen | last post by:
Is there a way to get the event handlers such that I can cache the info about handlers for a particular control, remove the handlers, do some code and restore the cached event handlers in VB.NET...
0
BarryA
by: BarryA | last post by:
What are the essential steps and strategies outlined in the Data Structures and Algorithms (DSA) roadmap for aspiring data scientists? How can individuals effectively utilize this roadmap to progress...
1
by: Sonnysonu | last post by:
This is the data of csv file 1 2 3 1 2 3 1 2 3 1 2 3 2 3 2 3 3 the lengths should be different i have to store the data by column-wise with in the specific length. suppose the i have to...
0
by: Hystou | last post by:
There are some requirements for setting up RAID: 1. The motherboard and BIOS support RAID configuration. 2. The motherboard has 2 or more available SATA protocol SSD/HDD slots (including MSATA, M.2...
0
marktang
by: marktang | last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However,...
0
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can...
0
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers,...
0
jinu1996
by: jinu1996 | last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven...
0
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows...
0
tracyyun
by: tracyyun | last post by:
Dear forum friends, With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.