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Information about events?

Where can I find *comprehensive* information about events?
I've been all through Microsofts developer pages, through the
VS.NET help but I can't find comprehensive, details information
about them.
For example, I'm working with a TreeView control. I've set up
2 even handler methods, one for "AfterSelect" and one for "Click".
In the "AfterSelect" handler method, I can access the TreeView
object to get state information and work with member attributes.
However, in the "Click" handler method, when I try to access
the very same attribute (or method or collection) that I successfully
accessed in the "AfterSelect" method, I get a null reference exception.
Why? I'm hoping someone could point me to a repository if (really
good) information that discusses events in detail.

Thanks for your time and assistance!

Christoph
Nov 16 '05 #1
1 1139
Hi, Christoph

I don't think you access same data in both methods. At least, doesn't seem
like that as per error you have. You can easily trace when which event
happens by adding Debug.Print or Console.WriteLine to the code and check
accesibility of data in debugger in both events.
And if you really need help, please strip down your code to the sample,
which can demonstrate the issue and post code here

HTH
Alex

"Christoph Boget" <jc*****@yahoo.com> wrote in message
news:u4**************@TK2MSFTNGP10.phx.gbl...
Where can I find *comprehensive* information about events?
I've been all through Microsofts developer pages, through the
VS.NET help but I can't find comprehensive, details information
about them.
For example, I'm working with a TreeView control. I've set up
2 even handler methods, one for "AfterSelect" and one for "Click".
In the "AfterSelect" handler method, I can access the TreeView
object to get state information and work with member attributes.
However, in the "Click" handler method, when I try to access
the very same attribute (or method or collection) that I successfully
accessed in the "AfterSelect" method, I get a null reference exception.
Why? I'm hoping someone could point me to a repository if (really
good) information that discusses events in detail.

Thanks for your time and assistance!

Christoph

Nov 16 '05 #2

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

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