Creating some associative array in JavaScript

Question

I have an object which contains an array, and I want it to contain an associative array so keys are strings. How can I do it?

This does not work:

{prof         


        

Answer 1

wanted to avoid console.log({profiles: { easy:{"example" : 1},advanced:{"example" : 1} })

Why? Is there a reason to avoid language-specific features?

If I told you you can do this (should be avoided):

var array = [];
array["foo"] = "bar";
array.foo // -> bar

The problems with it:

array.length // -> 0

So, even if you can apply properties to mostly everything in JavaScript like:

var str = "hello";
str.type = "greetings";

you shouldn't screw the language...

This is the normal way of creating key:value maps, objects:

var obj = {foo: "bar"}
obj.foo // -> bar

Why not do it just like the language is designed to?

Answer 2

JavaScript doesn't have "associative arrays".

It has objects, which you can store values on in named properties.

It has arrays, which store an ordered set of values via integer properties. Since they are a type of object, you can also store named values on them (but you can't create them using the literal syntax, only add them after the array is created) but this isn't considered good practise and they will be ignored by just about anything that has special case handling for arrays.

As of ES6 it also has Maps which are similar to objects in that you can give them named values, but also to arrays in that order is preserved. There is no literal syntax for creating a Map.