Storage: key() method
Baseline
Widely available
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.
Syntax
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 string 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 (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.
Specifications
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| HTML # dom-storage-key-dev |
Browser compatibility
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Legend
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- Full support
- Full support