Javascript associavtive array

Question

I want to create an array for javascript

var person = {firstName:"John", lastName:"Doe", age:46};
var person = {firstName:"Peter", lastName:"Toh", age:20};

For example I want to create

person[1].firstName return me John
person[2].firstName return me Peter

How do I actually declare my javascript to make the 2 element works.

Erm... `var person = [{firstName:"John"},{firstName:"Peter"}];` gives `person[0].firstName` as `John`. Note that arrays are zero-based. — Niet the Dark Absol, Nov 12 '14 at 15:36
There are many good JavaScript tutorials available on the Internet. I recommend MDN: [MDN - Arrays](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Predefined_Core_Objects#Array_Object). — Felix Kling, Nov 12 '14 at 15:51

Philipp · Answer 1 · 2014-11-12T15:42:30.157

You aren't creating an associative array, you are creating an array of objects. You can either initialize it with an array literal:

var person = [
     {firstName:"John", lastName:"Doe", age:46},
     {firstName:"Peter", lastName:"Toh", age:20}
];

(keep in mind that arrays in javascript start with zero, so person[0] will be John and person[1] will be Peter).

or you can create an empty array and then add the entries afterwards. This allows you to choose the indexes freely:

var person = [];
person[1] = {firstName:"John", lastName:"Doe", age:46};
person[2] = {firstName:"Peter", lastName:"Toh", age:20};

score 0 · Answer 2 · edited May 23 '17 at 12:05

Use an array literal to create an Array:

var persons = [{firstName:"John", lastName:"Doe", age:46},
               {firstName:"Peter", lastName:"Toh", age:20}];

Notice that arrays are zero-indexed in JavaScript, so you'd access it like this:

person[0].firstName; // John
person[1].firstName; // Peter

2 Answers2