Below is the example of the Array keys() method.

• Example:
  
  

  
  
  

  <script>       // Taking input as an array A     // containing some elements.    var A = [ 5, 6, 10 ];       // array.keys() method is called    var iterator = A.keys();       // printing index array using the iterator    for (let key of iterator) {     document.write(key + ' ');    } </script>

• Output:

  0 1 2

The array.keys() method is used to return a new array iterator which contains the keys for each index in the given input array.

Syntax:

array.keys()

Parameters: This method does not accept any parameters.

Return Values: It returns a new array iterator.

Below example illustrate the Array keys() method in JavaScript:

• Example:

  var A = [ 'gfg', 'geeks', 'cse', 'geekpro' ];
  var iterator = A.keys(document.write(key + ' '));

  Output:

  0 1 2 3

Code for the above method is provided below:
Program 1:

Output:

0 1 2 3 

Program 2:

Output:

0 1 2 3 4 5 6 

Supported Browsers: The browsers supported by JavaScript Array keys() method are listed below:

• Google Chrome 38.0
• Microsoft Edge 12.0
• Mozilla Firefox 28.0
• Safari 8.0
• Opera 25.0