field API

Extending Drupal 8 Fields That Contain Data

The Exception

Data protection is one of the primary advantages of Drupal, but sometimes there are exceptions to the rule and you might need to modify a field to account for some change in business needs. There are a few rule bends (read hacks) that can be done to circumvent Drupal's checks and still maintain data integrity. You should only perform this when extending a field or changing something reasonable that is allowed by the database server. For example, expanding a varchar length or changing unformatted string into a formatted text field.

Drupal 7 Tutorial: Creating Custom Formatters with the Field API

Custom formatters are a great way to control the output of your fields. In this tutorial I'm going to use an example that takes a user's Facebook URL as the input and outputs a button of the Admin's choosing, along with an option to open the link in a new window. To get started, we'll need to get a module skeleton sketched out. You'll need to create these two files:

  • facebooklink.info
  • facebooklink.module

The first file, facebooklink.info, can be fairly simple: