The key()
method of the Storage
interface, when passed a number n, returns the name of the nth key in a given Storage
object. The order of keys is user-agent defined, so you should not rely on it.
Syntax
var aKeyName = storage.key(index);
Parameters
index
- An integer representing the number of the key you want to get the name of. This is a zero-based index.
Return value
A DOMString
containing the name of the key. If the index does not exist, null
is returned.
Examples
The following function iterates over the local storage keys:
function forEachKey(callback) { for (var i = 0; i < localStorage.length; i++) { callback(localStorage.key(i)); } }
The following function iterates over the local storage keys and gets the value set for each key:
for(var i =0; i < localStorage.length; i++){ console.log(localStorage.getItem(localStorage.key(i))); }
Note: For a real world example, see our Web Storage Demo.
Specifications
Specification | Status | Comment |
---|---|---|
HTML Living Standard The definition of 'Storage.key' in that specification. |
Living Standard |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
key | Chrome Full support 4 | Edge Full support 12 | Firefox Full support 3.5 | IE Full support 8 | Opera Full support 10.5 | Safari Full support 4 | WebView Android Full support Yes | Chrome Android Full support 18 | Firefox Android Full support 6 | Opera Android Full support 11 | Safari iOS Full support 3.2 | Samsung Internet Android Full support 1.0 |
Legend
- Full support
- Full support