Sorts an array based on a property. Reversible.

Sort on object properties

//Based on http://jsfiddle.net/dFNva/1/

var events = [
        {
		event_name: "Recurring",
		start_date_time: new Date('Fri May 17 2013 01:00:00 GMT-0400 (EDT)'),
		rating: '4.1'
	}, {
		event_name: "Morning Dive",
		start_date_time: new Date('Tue May 14 2013 02:00:00 GMT-0400 (EDT)'),
		rating: '1.0'
	}, {
		event_name: "Beginner's Course",
		start_date_time: new Date('Mon May 13 2013 08:30:00 GMT-0400 (EDT)'),
		rating: '2.2'
	}, {
		event_name: "Morning Dive",
		start_date_time: new Date('Mon May 13 2013 08:30:00 GMT-0400 (EDT)'),
		rating: '3.5'
	}, {
		event_name: "Morning Dive 2",
		start_date_time: new Date('Tue May 14 2013 02:00:00 GMT-0400 (EDT)'),
		rating: '4.0'
	}, {
		event_name: "Fizzlepop 5",
		start_date_time: new Date('Fri May 17 2013 01:00:00 GMT-0400 (EDT)'),
		rating: '5.0'
	}
];

var sort_by = function(field, reverse, primer){
	var key = function (x) {return primer ? primer(x[field]) : x[field]};

	return function (a,b) {
		var A = key(a), B = key(b);
		return ( (A < B) ? -1 : ((A > B) ? 1 : 0) ) * [-1,1][+!!reverse];
	}
}

console.log('Sort by Name');
events.sort(sort_by('event_name', true, function(a){return a.toUpperCase()}));
for (i=0; i<events.length; i++) {
    console.log(events[i].event_name, events[i].start_date_time, events[i].rating);
}

console.log('Sort by Date');
events.sort(sort_by('start_date_time', true, function(a){ return a }));
for (i=0; i<events.length; i++) {
	console.log(events[i].start_date_time, events[i].event_name, events[i].rating);
}

console.log('Sort by Rating');
events.sort(sort_by('rating', true, parseFloat));
for (i=0; i<events.length; i++) {
	console.log(events[i].rating, events[i].start_date_time, events[i].event_name);
}