I am using gravity forms for a user registration process on a client’s site and it occurred to me they may want to limit who is eligible to submit a registration form on the site. This would cut down on registration spam, make it easier for the administrator to approve new accounts and further secure their members-only area.
To accomplish this I used the gform_field_validation function to have the user type in a passphrase and match it to an already pre-defined phrase we have setup.
Choose a field to use are your passphrase in Gravity Forms and note the field ID. In my example the field ID is : gform_2_9
// Add a passphrase to registartion field in gravity forms
add_filter( 'gform_field_validation_2_9', 'custom_validation', 10, 4 );
function custom_validation( $result, $value, $form, $field ) {
$arrWhitelist = array('passphrse'); // This can also be multiple commma seprated values for multiple passwords like array('pass1', 'pass2', 'pass3')
if ( $result['is_valid'] && !in_array( $value, $arrWhitelist )) {
$result['is_valid'] = false;
$result['message'] = 'Please enter the correct passphrase to submit this form.'; // Our error message
}
return $result;
}
Add the above code to your functions.php file and be sure to change the field ID from _2_9 to whatever your field value is.