I have a requirment where the user should not be allowed to enter more than 1000 partnumbers in a textbox prompt. or it should show an alert when he tries to enter more than 1000 part numbers.
You're actually going to ask a user to select - by hand - up to 1000 selections in a textbox (why exactly 1000 anyway) ? Is this a hoax? :o
Surely partnumbers are related to some sort of category/ies, so you can use pre-selects aka cascading prompts?