How to Check If Local Storage Item is Set

March 28, 2020

javascript

Check if Local Storage Item is set

1.if (localStorage.getItem("yourItem") == null) {
2.
3.}

The getItem method on the localStorage object in HTML5 specifies that if an item does not exist then it will return null. All we have to do is check whether the method returns null or not.

Examples

1.if (localStorage.getItem("username") == null) {
2.    console.log("Item does not exist");
3.}
4.// Item does not exist

1.localStorage.setItem("username", "cody");
2.
3.if (localStorage.getItem("username") == null) {
4.  console.log("Item does not exist");
5.}
6.//

Function for checking local storage

We can encapsulate this in a function as follows:

1.const isInStorage = str => localStorage.getItem(str) !== null;

Examples

1.if (isInStorage("username")) {
2.    console.log("Item does not exist");
3.}
4.// Item does not exist

1.localStorage.setItem("username", "cody");
2.
3.if (isInStorage("username")) {
4.  console.log("Item does not exist");
5.}
6.//