Validating a method
In some situations, you may wish to run validation checks against a field only if that field is present in the input array.
First, create a Let's assume our web application is for game collectors.
For example, you may wish to require a given field only if another field has a greater value than 100.
Or, you may need two fields to have a given value only when another field is present.
The field under validation must exist on a given database table. The field under validation must be an IPv4 address.
The field under validation must be an IPv6 address.