Storage.setItem

The setItem() method of the Storage interface, when passed a key name and value, will add that key to the storage, 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 quota to 0 bytes in private mode, contrary to other browsers, who 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');
}

Specifications

Browser compatibilityUpdate compatibility data on GitHub

See also

• Storage.getItem()
• Storage.removeItem()
• Using the Web Storage API