thankyou or your response
what is want is-
1.user should select any value
2.value then pass onto the variable
3. if user closes the input box or select [OK] without selecting any value, it needs to throw an error, error should be visible to user(to select any value or any system built)
4. continuously pop the input dialogue until the correct value gets selected by the user.
is (do while) is the only way to solve this?
your insights are much appreciated.