DateTimePicker valueChanged event.

Question

 

Hi, I have a DateTimePicker on one of my forms and when the user change the date I have some code in the _ValueChanged event handler.

Part of the code has a Confirm MessageBox that allows the user to confirm whether he wants to change the date or not.  If the user selects no then I change the date back to the original...

Code

...
resetDate = true;
dtpExpVector.Value = prevDate;
resetDate = false;
...

I deal with the new _ValueChanged event fired by dtpExpVector.Value = prevDate using the booleans above. 

My problem is that for some reason the _ValueChagned event appears to be getting fired an extra time at the end with the date the user selected.  Does anybody know why?

It appears to be the line dtpExpVector.Value = prevDate; that is causing the extra event to be fired.  I expect it to fire 1 event but it actually seems to fire 2.

For example if the DateTimePicker shows 22nd March and I change it to 9th March I get the following events:

Event 1: _ValueChanged(9th March)

If the user then rejects the change the line dtpExpVector.value = prevDate; is called so:

Event 2: _ValueChanged(22nd March).

This is what I expect but a 3rd Event gets called:

Event 3: _ValueChanged(9th March).

It is this 3rd event that I can't explain.

Thanks.

Wallace