FrankHunter wrote: ...
Users can add new fields while they are filling the registration?
For example... a new field for more than one telephone number?
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My case: i have restaurants like members of a website and I need new users can add lines for your menu... every menu a line.
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Is for the public while they are filling the registration and, off course, for actually registers users.
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Not sure if I got your idea...
but Core-Fields-AJAX is neither a new field type, nor it allows to duplicate or repeat any field. It is not used for registration process. It is used for editing profile fields.
It allows the user to change the field value in place. No need to go to edit-user-profile page. Usually, the user edits the fields on a special page/form. All fields in one go. With Core-Fields-AJAX you can edit the data right on your profile. One by one.
Your application sounds like this:
You want to add/repeat fields. This is not possible. An admin has to create all fields that your users might need. You can decide if you see the fields on registration OR after registration.
If you dont´t want to show too many fields at once... there is a workaround: CB Conditional plugin. It allows you to show more fields based on another field i.e:
(Checkbox) Are you a movie fan? YES/NO
YES -> Then show 3 additional Text input fields for your 3 favourite movie titles