In this recipe, I’ll show you how to implement a user input validation that sets the upper limit of checkbox selection. This validation is based on the Schema-Woven Validation (SWV) mechanism, so it has some big advantages over the previous filter-based validation, such as:

• You can use validation rules already defined by SWV, so you don’t need to code the validation logic yourself.
• Once you create an SWV validation rule, the rule can work anywhere as long as SWV is supported. On the other hand, filter-based validation only works on the server side.