GlideForm & GlideList in ServiceNow: Client Script Guide

In the previous topic, we learned about client-side scripting and the main Glide classes used in ServiceNow. To understand how Glide classes work in different ways and processes, it is important to understand the different types in detail. This topic focuses on GlideForm and GlideList in ServiceNow.

GlideForm helps you control how a record form looks and behaves, while GlideList helps you work with lists of records. Understanding both will help you write better client scripts in ServiceNow.

What is GlideForm in ServiceNow?

GlideForm(g_form) is a client-side JavaScript API and global object that provides methods to customize record forms directly inside the user’s browser.

The g_form object is available automatically in supported client scripts, so you do not need to create it yourself.

Some important things to remember while using GlideForm are: 

• GlideForm methods are meant for the client side only. Never use them in server-side scripts.
• Some methods may behave differently in Catalog Client Scripts or Wizard Client Scripts. Check the documentation for the specific method before using it.
• With g_form, you can read and set values, show or hide fields, make fields mandatory or read-only, show messages, change choice lists, and save the form.

GlideForm Methods

GlideForm methods in ServiceNow provide several ways to control form behavior. These client script form methods help you perform common tasks without writing everything from scratch.

The following table covers some of the most useful GlideForm methods in ServiceNow:

What is GlideList (g_list)?

GlideList in ServiceNow is a JavaScript class used to manipulate and interact with lists on a web page. The g_list object provides methods for interacting with supported list interfaces. You can read the current filter, get selected record IDs, change list filters, and refresh a list.

For example, you can use GlideList when you want to filter an Incident list to show only active incidents.

GlideList Methods

Here is a GlideList ServiceNow most commonly used methods:

Note: GlideList methods are not available in every ServiceNow interface or scripting context. Check the current API documentation before using them. Some methods and behaviors differ between classic interfaces and Next Experience.

GlideForm Vs GlideList

Practical Examples with GlideForm & GlideList

These GlideForm examples use the Incident table. Field names and values may differ in your instance, so test them in a personal developer instance first.

Example 1: Hide a field on a new record (OnLoad)

Javascript

function onLoad() {

    if (g_form.isNewRecord()) {

        g_form.setDisplay('close_notes', false);

    }

}

Example 2: Make fields mandatory when an incident is resolved (OnChange)

Run this on the state field.

javascript

function onChange(control, oldValue, newValue, isLoading, isTemplate) {

    if (isLoading || newValue === '') {

        return;

    }

    if (newValue == '6') {   // 6 = Resolved

        g_form.setMandatory('close_code', true);

        g_form.setMandatory('close_notes', true);

        g_form.addInfoMessage('Please add the close code and close notes.');

    } else {

        g_form.setMandatory('close_code', false);

        g_form.setMandatory('close_notes', false);

    }

}

Example 3: Stop a save if data is missing (OnSubmit)

javascript

function onSubmit() {

    if (g_form.getValue('state') == '6' && g_form.getValue('close_notes') == '') {

        g_form.showFieldMsg('close_notes', 'Close notes are required to resolve this incident.', 'error');

        return false;   // stops the save

    }

    return true;

}

What’s Next?

After understanding the GlideForm and GlideList. In the next topic, we will understand GlideAjax, GlideUser and GlideDialogWindow in ServiceNow through a practical Client Script guide.