How to sort a Javascript object, or convert it to an array?

Question

I have some JSON data that I get from a server. In my JavaScript, I want to do some sorting on it. I think the sort() function will do what I want.

However, it seems

Answer 1

Array.prototype.slice.call(arrayLikeObject)

is the standard way to convert and an array-like object to an array.

That only really works for the arguments object. To convert a generic object to an array is a bit of a pain. Here's the source from underscore.js:

_.toArray = function(iterable) {
    if (!iterable)                return [];
    if (iterable.toArray)         return iterable.toArray();
    if (_.isArray(iterable))      return iterable;
    if (_.isArguments(iterable))  return slice.call(iterable);
    return _.values(iterable);
};

_.values = function(obj) {
    return _.map(obj, _.identity);
};

Turns out you're going to need to loop over your object and map it to an array yourself.

var newArray = []
for (var key in object) {
    newArray.push(key);
}

You're confusing the concepts of arrays and "associative arrays". In JavaScript, objects kind of act like an associative array since you can access data in the format object["key"]. They're not real associative arrays since objects are unordered lists.

Objects and arrays are vastly different.

An example of using underscore:

var sortedObject = _.sortBy(object, function(val, key, object) {
    // return an number to index it by. then it is sorted from smallest to largest number
    return val;
});

See live example