Need help in validation

Question

Hi,
In my application, I haev menu items. one of the menu item name is CLOSE. I also have a textbox in my UI. I want to do soem validation on my textbox on lost focus. I am able to do this but I am not able to handle one case. Scenario is like this: When user type value in textbox and then quickly clicks on CLOSE menu item, in that case I don't want my textbox validation to fire.
How to achieve this ?