Add validation before form submission

[shrutika.kole]

I had connected gravity form with REST API. Now to need to add validation like - i have to save gravity form details on rest api first and after that we need to add the entries in gravity form. And if in case any error or validation on api side then we don’t want to add that into gravity form entry

[simonc]

Have you tried validating the fields on submission?

gform_field_validation