How to use "X" (close) button of a vi as an event?

[mnx]

I want to have a fuction in my vi such that whenever a user writes anything on a file(a table present on fp)and tries to close the vi without saving the file, he should get a notification to save the file as we get in Microsoft office (shown in attached image as reference).Any takes on this??

[nathand]

Yes - you need to use an event structure with the Panel Close? event.

[crossrulz]

As stated, you need to use an event structure.  Choose the "Panel Close?" event under "This VI".  I recommend using the filter event (will have a red arrow next to it, plus the ? in the name) so that you can discard the event and leave your panel open if you so desire.