Question

195

How can I check if a localstorage variable is null or undefined?

rated 0 times [ 199] [ 4] / answers: 1 / hits: 55365 / 12 Years ago, thu, november 15, 2012, 12:00:00

I have this code:

var sideBar = localStorage.getItem('Sidebar');

I want to check if sideBar is defined and not null in an if statement. I am a bit confused I know there's a: sideBar == undefined and sideBar != null

but is there a good way for me to do this test for both of these inside an if:

if (??)

Answers

Only authorized users can answer the question. Please sign in first, or register a free account.

antonb

Add To Favorites

Follow

Total Points: 424

Total Questions: 104

Total Answers: 101

Location: Serbia

Member since Tue, Jul 26, 2022

2 Years ago

answered 12 Years ago luna · Accepted Answer

best practice for checking if a variable is defined and not null:

if (typeof sideBar !== 'undefined' && sideBar !== null)

edited realized you're not checking if something is undefined, you're checking that it's defined, so edited again to answer your request more accurately