For the attribute for that field you could add
data-after::,
Which would display a comma.
However that only applies to the display of that field
To put all the data in one field you could do something like…
First create a field in pdp called ‘all_data’ or something like that.
Then write some php. Download a php snippet plugin.
<?php
// Get all your required fields from WP
$wp_user_id = get_current_user_id();
$current_user = wp_get_current_user();
$wp_username = $current_user->user_login;
$wp_email = $current_user->user_email;
$wp_firstname = $current_user->user_firstname;
$wp_lastname = $current_user->user_lastname;
$pdb_id=Participants_Db::get_record_id_by_term('username',$wp_username);
//Now combine the data (Concatenate)
$all_data=$wp_firstname.' '.$wp_lastname.', '.$wp_email.', '.$wp_user_id
// This will display something like
// Joseph Campbell, [email protected], 192
//Now write the data to pdb
data['all_data']=$all_data;
$data = array();
Participants_Db::write_participant($data,$pdb_id);
?>
You can then display this on the front end using
echo $all_data;