Check wheter a button or textbox is clicked.

I have two text boxes (txt1, txt2) and an exit button (btnExit)
In txt1.Leave event; i have some validations. If validation fails then I keep the fous on txt1.
If btnExit is clicked then I do not want to execute the validation and instead close the application.. How do I do it?

Do not enable the button until the validation has been completed.

The button btnExit needs to be enabled since it's an EXIT button and can be clicked regardless of what was entered in txt1.text.

Sorry....I misunderstood you....

If your validations are in the Leave event they will fire immediately after you leave the textbox. It does not matter what you do next. The validations will fire.

What do the validations consist of?

txt1.text accepts numeric value (zip code); I validate the zip code.