Javascript associative array keys with starting 0 [duplicate]

Because of the leading 0's you have a Javascript object rather than a Javascript array. Javascript objects don't have an order. They are a key->value map. You can convert your values to numbers and then have a sparse array instead:

var testArr = []; testArr[+"0000"] = "00000 - COST CENTER - BALANCE SHEET"; testArr[+"0017"] = "0017 - Test Team"; testArr[+"00033"] = "00033 - Test Team "; testArr[+"87210"] = "87210 - OFFICE OF THE PRESIDENT"; // Results in: [ 0: "00000 - COST CENTER - BALANCE SHEET", 17: "0017 - Test Team", 33: "00033 - Test Team ", 87210: "87210 - OFFICE OF THE PRESIDENT" ] 

If you need to maintain the leading '0's, or if your keys are not necessarily always numeric, you should use an array of objects instead:

var testArr = []; testArr.push({id: "0000", name: "00000 - COST CENTER - BALANCE SHEET"}); testArr.push({id: "0017", name: "0017 - Test Team"}); testArr.push({id: "00033", name: "00033 - Test Team "}); testArr.push({id: "87210", name: "87210 - OFFICE OF THE PRESIDENT"}); 

Then you maintain the order and can loop through in order like this:

for(var i = 0; i < testArr.length; i++){ console.log(testArr[i].id + ': ' + testArr[i].name); } 

Depending on how you need to use it, you could also do something like this:

var testArr = []; testArr.push({ id: "0000", value: "00000 - COST CENTER - BALANCE SHEET"}); testArr.push({ id: "0017", value: "0017 - Test Team"}); testArr.push({ id: "00033", value: "00033 - Test Team "}); testArr.push({ id: "87210", value: "87210 - OFFICE OF THE PRESIDENT"}); 

Your array would stay in the order you created it, and your IDs would stay intact. You would of course lose the ability to access the item like an associative array using the id.

Edit in response to your comment:

Objects in javascript are the same thing as associative arrays. So when you do this:

testArr["0000"] = whatever

It's exactly the same as

testArr.0000 = whatever

Given that, you can see why there's no sorting. Properties in an object have no sort order.

What I'm doing differently is pushing objects into an array (an actual array, not an associative array/object), so the indexing is done as 0, 1, 2 (since it's an array), and the order is preserved.