This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
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.
key(index)
indexAn integer representing the number of the key you want to get the name of. This is a zero-based index.
A string containing the name of the key. If the index does not exist, null is returned.
The following function iterates over the local storage keys:
function forEachKey(callback) {
for (let 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 (let i = 0; i < localStorage.length; i++) {
console.log(localStorage.getItem(localStorage.key(i)));
}
Note: For a real-world example, see our Web Storage Demo.
| Specification |
|---|
| HTML> # dom-storage-key-dev> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
key |
4 | 12 | 3.5 | 10.5 | 4 | 18 | 6 | 11 | 3.2 | 1.0 | 4.4 | 3.2 |
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https://developer.mozilla.org/en-US/docs/Web/API/Storage/key