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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Using Array Indices

Sam Blaha
Sam Blaha
15,146 Points

Do negative indices work in JavaScript?

I'm new to JavaScript but have some experience in other languages. Isn't it possible to grab the last index using -1? It failed me here....

script.js
var players = ['Jim', 'Shawna', 'Andrew', 'Lora', 'Aimee', 'Nick'];
console.log(players[0]);
console.log(players[-1]);
index.html
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

Yes, there's a few ways to get the last item in an array.

An array index starts at 0, but the length will return 6.

The length property of an array does not start off on the 0 index. Therefore, if you type console.log(players[players.length]) it will come back undefined because there's nothing at index 6. Index stops at 5.

With that in mind you can use the example below.

console.log(players[players.length - 1]);