So you want to prevent a user from typing in a specific value in a field and display an error telling them they can't use that value if they do?
If so, what you want to do is custom validation. There is an API hook called gform_validation that you can use to write your own custom validation for a field. You can find documentation for this hook here:
There is also a tutorial on how to write custom validation in a tutorial here:
We can't take into account all kinds of custom use validation which is why we have a hook that allows developers to write their own custom validation for custom use cases.
Posted 10 years ago on Tuesday May 24, 2011 | Permalink