[google-apps-script] How to define global variable in Google Apps Script

I see most examples from Google is they use only functions in a single giant script.

e.g. https://developers.google.com/apps-script/quickstart/macros

But in our style, we usually write all functions under a single namespace, such as

MyCompany = (MyCompany || {});
MyCompany.init = function () {

function onOpen() {
    var spreadsheet = SpreadsheetApp.getActiveSpreadsheet();
    var menus = [{
        name: "Init",
        functionName: MyCompany.init
    spreadsheet.addMenu("Test", menus);

However, when I run the code above, it return

"MyCompany is not defined."

How to solve?

The answer is

You might be better off using the Properties Service as you can use these as a kind of persistent global variable.

click 'file > project properties > project properties' to set a key value, or you can use

PropertiesService.getScriptProperties().setProperty('mykey', 'myvalue');

The data can be retrieved with

var myvalue = PropertiesService.getScriptProperties().getProperty('mykey');

Similar questions with google-apps-script tag:

Similar questions with google-sheets tag:

Similar questions with global-variables tag:

Similar questions with google-docs tag: