Using an integer as a key in an associative array in JavaScript

Question

When I create a new JavaScript array, and use an integer as a key, each element of that array up to the integer is created as undefined.

For example:

v         


        

Answer 1

Sometimes I use a prefixes for my keys. For example:

var pre = 'foo',
    key = pre + 1234

obj = {};

obj[key] = val;

Now you don't have any problem accessing them.