JavaScript Array keys()

The syntax of the keys() method is:

arr.keys()

Here, arr is an array.

keys() Parameters

The keys() method does not have any parameters.

Return value from keys()

• Returns a new Array iterator object.

Example: Using keys() method

const languages = ["JavaScript", "Java", , "C++", "Python"];
let iterator = languages.keys();

for (let key of iterator) {
  console.log(key);
}

Output

0
1
2
3
4

Note that the third empty element is not ignored.

Recommended Reading: JavaScript Array values()