Custom Error Handling in Forminator Forms

Hi @domelem1231,

Hope this message finds you well.

I want to add an entry to a database when a user clicks the submit button on my Forminator form. I have already managed to do this successfully.

Forminator has a Database store feature already, and if an error occurs it will return a default error in the front-end and the form will be not submitted, this is in the Settings tab:

If you are not referring to this feature and you managed a custom code to insert the data in a different way, we will need to check the full code so we can provide you with the right solution.

if the database insertion fails (which can happen for various reasons), I want to notify the user of this error and prevent the Forminator post from proceeding (e.g., stop the emails configured in Forminator from being sent).

Guessing you are storing the data in a different way using a custom code the hooks:

forminator_form_submit_response
forminator_form_ajax_submit_response

Runs after the form has been successfully submitted, for either Ajax or PHP methods, resulting in Forminator Pro >> Email Notifications have been sent.

About the code you shared, after testing it returned an error on my test form, it needs some tweaks:

add_action("forminator_form_after_handle_submit", "on_forminator_form_submit", 20, 2 );
add_action("forminator_form_ajax_submit_response",	"on_forminator_form_submit", 20, 2); 
  
function on_forminator_form_submit($response, $form_id) {
	if ( 1609 != $form_id ) { // Please change the form ID.
		return $response;
	}

	// Retrieve the content of the Forminator form

    // Insert data into the database

    // If the database insertion is successful

    if (db_insertion_successful()) {
		//add your custom succesful message here, otherwise leave empty 
		$response['message'] = 'Success custom message';
	} else {
		// Return a custom error message to display in the form
		$response['message'] = 'Failed custom message';
		// Prevent the emails configured in Forminator from being sent
		
		// TODO: Implement this part
	}
  
	return $response;
 }

In case you want to prevent the form submission the code would be this:

add_filter( 'forminator_custom_form_submit_errors', function( $submit_errors, $form_id, $field_data_array ) {
    // Add your form IDs here.
    $form_ids = array( 6 );
    // Change this to the message that you want to show.
    $message = 'You cannot submit now.';
    if ( in_array( intval( $form_id ), $form_ids, true ) ) {
        $result = store_data( $field_data_array );
        if ( $result ) {
            $submit_errors[]['submit'] = $message;
            $GLOBALS['form_error'] = true;
        } else {
            $GLOBALS['form_error'] = false;
        }
    }
    return $submit_errors;
},15,3);

function store_data( $form_id ){
    // add your custom code to save forminator data
    //$entry_save
    if ( $entry_save ) { //if success return true
        return true;
    }
    return false;
}

add_filter( 'forminator_custom_form_invalid_form_message', 'wpmudev_invalid_form_error_response_submit', 10, 2 );
function wpmudev_invalid_form_error_response_submit( $invalid_form_message, $form_id ){
    if ( $form_id != 6 ) { //Change your form ID
        return $invalid_form_message;
    }

    if ( $GLOBALS['form_error'] ) {
        $invalid_form_message = __( 'You cannot submit now.', 'forminator' );
    }

    return $invalid_form_message;
}

Let us know the results or if you require additional information.

Best regards,
Laura