Storage.setItem()

The setItem() method of the Storage interface, when passed a key name and value, will add that key to the given Storage object, or update that key's value if it already exists.

Syntax

storage.setItem(keyName, keyValue);

Parameters

keyName

A DOMString containing the name of the key you want to create/update.

keyValue

A DOMString containing the value you want to give the key you are creating/updating.

Return value

undefined.

Exceptions

setItem() may throw an exception if the storage is full. Particularly, in Mobile Safari (since iOS 5) it always throws when the user enters private mode. (Safari sets the quota to 0 bytes in private mode, unlike other browsers, which allow storage in private mode using separate data containers.) Hence developers should make sure to setItem().

Example

The following function creates three data items inside local storage.

function populateStorage() {
  localStorage.setItem('bgcolor', 'red');
  localStorage.setItem('font', 'Helvetica');
  localStorage.setItem('image', 'myCat.png');
}

Note: To see this used within a real world example, see our Web Storage Demo.

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
setItem
4
12
3.5
8
10.5
4
≤37
18
6
11
3.2
1.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/Storage/setItem