Question

I have been reading that in Javascript :

• Everything is an object (except primitives such as number,string, boolean, null & undefined)
• Objects can be treated as associative arrays.

From what I conclude, Array.isArray() should return true for everything (with primitive exceptions aforementioned). What wrong did I understand ?

Thanks !

Answer 1

There’s a difference between an Object and an Array. An Array is actually an Array Object. It has different methods than other objects. A String is a String object. However, you can access objects as if they were an array. Take the following object

var obj = {
    value1: 'Some Value',
    value2: 'Some Other Value'
    };

You can get values like

obj['value1'];
obj['value2'];

This doesn’t mean that it’s an Array Object, it just has a different way of accessing it

isArray() checks if the object is an Array Object, not if you can access it like an array