Lodash / Underscore sort object keys. Like _.sortBy(), but on keys instead of values, returning an object, not an array. Defaults to alphanumeric sort.

example.js

var obj = {b: 3, c: 2, a: 1};

_.sortKeysBy(obj);
// {a: 1, b: 3, c: 2}

_.sortKeysBy(obj, function (value, key) {
    return value;
});
// {a: 1, c: 2, b: 3}

sortKeysBy.js

_.mixin({
  'orderKeysBy': function (obj, comparator, order) {
    if (_.isString(comparator) && _.isEmpty(order)) {
      order = comparator;
      comparator = null;
    }
    var keys = _.orderBy(_.keys(obj), function (key) {
      return comparator ? comparator(obj[key], key) : key;
    }, order);

    var values = _.map(keys, function (key) {
      return obj[key];
    });

    return _.zipObject(keys, values);
  }
});