Question

I have 3 TextBoxes on the page. How do I setup one validator (and what’s kind of validator?) to validate each of TextBoxes on client side?

First textBox must contains only 1-3 number of digits, second – infinite number of digits, third – 0-5 number of digits

Answer 1

It would be better to use different validators for different text boxes.
Use 3 validators for each with display message as * sign.

Then use Validation Summary control to print a single message for all of them, as you want a single message to be displayed for all. Refer this link: MSDN Validation Summary

Check this too: Validation Summary to work with client-side validations