Tree View nodes

Hey Guys, i don't why i am not getting this but i can't figure out how to know the node.key when a user 'right-clicks' on a tree node (i wanna appear a menu when he right clicks on this node just like when you right-click on a folder in windows explorer) ?
So i wanna know when he clicks and when he right-clicks, get it ?

Thanks guys, i do appreciate.

I don't have the exact code here, since I am at work, and I might be wrong but couldn't you just put something in the forms private sub mouse_down click() or right_click() section?

Speaking of treeview, how can I manipulate the form when different nodes are selected?