Question

that is a question I have been asking myself for a while.

Giving a certain flow of events, can I when handling one of them, stop the next ones to be raised?

For example, when collapsing a node which child was selected in a treeview (winform), the events are raised like that:

• BeforeCollapse
• BeforeSelect
• AfterSelect
• AfterCollapse

I could stop them by using a class member, but I was wondering whether there was a built-in function or just another way (a more elegant way) to achieve this, by acting directly on the events queue.

Any idea?

Answer 1

Not easily, no. The order of the events firing is controlled by the TreeView control class, and there is no built-in way to prevent events from firing. But you have a couple of options:

1. Create your own TreeView class that inherits from the base class,
   then add a bool property to prevent the events from processing.
   Then you can override BeforeCollapse, etc. to check the bool
   before calling base.BeforeCollapse.
2. Just create a bool flag, and check the flag in each of the events.