I've figured out how to make a custom form, no problem. There are four things that I'd like to do with the information in the form:
- I'd like to make filling out the custom form a mandatory precondition for registration. Leaving the form blank means that the registration process stops.
- I'd like to define a mandatory length of the custom form, say 32 characters. (So, for example, if someone writes 'house' in the custom form (in an attempt to bypass it), registration will fail because 'house' isn't 32 characters).
- I'd like to call a custom PHP script using the data in the custom form in order to "check" the information, and depending on the result, assign the user to a group. (This means that the custom php script would have to pull out the information stored in this particular field from the database, process it, and then turn a flag in the database for the user group).
- After the user has been assigned, the user will no longer be able to edit this custom field.