I have a form embeddend in all posts of a custom post type. In the form is a checkbox group ($field['22']) that is populated dynamically using gform_pre_submission. Its values are the usernames of any registered user who has commented on the post. This is working perfectly.
Obviously, depending on the number of people who comment, there could be anything from 1 to dozens of options available. I need to take the selected values ONLY and save them to a custom field.
I am using a function on gform_post_submission already with this form, and it's working fine for other fields, but I am not clear how to retrieve an array of selected values from this checkbox group to add to a custom field.