ListBox.SelectedIndexChanged - can you determine i

Question

My question is similar to this: How to prevent ListBox.SelectedIndexChanged event?, but I want to ask it a different way.

Is there a simple way to determine if the 'SelectedIndexChanged' is coming from the user as opposed to initiated through code (e.g. ListBox.SelectedIndex = x)?

Answer 1

For me, the 'SelectionChangeCommitted' event was better suited for my purposes. It fires when a selection in the drop down is selected. This is the easiest way to handle the specific case when the end-user initiates the change. SelectedIndexChanged is to capture all cases.

Answer 2

Property change listeners don't distinguish between causes of a property change. It's a common problem. Setting a flag is the way to do it.

I do wish that there was a way to set values without firing property change events. But then, people argue that it breaks the whole object-oriented model, because it effectively allows you to change a field directly, without using a property.

Answer 3

As far as I know, no, there's no simple way built-in. The best I've been able to do is set a flag just before changing it in code and then letting the event handler reset the flag and return.

I suppose you could start examining the call stack and see if it's originating somewhere in your own code or not, but I'm not sure how much it's worth the effort.