jQuery, random div order

Answer 1

Try this:

http://jsfiddle.net/UgX3u/33/

$("div.container div").sort(function(){
    return Math.random()*10 > 5 ? 1 : -1;
}).each(function(){
    var $t = $(this),
        color = $t.attr("class");
    $t.css({backgroundColor: color}).appendTo( $t.parent() );
});

.sort is applied to jQuery like this:

$.fn.sort = [].sort

Since it doesn't perform like other jQuery methods, it isn't documented. That does mean it is subject to change, however I doubt it will ever change. To avoid using the undocumented method, you could do it like this:

http://jsfiddle.net/UgX3u/37/

var collection = $("div.container div").get();
collection.sort(function() {
    return Math.random()*10 > 5 ? 1 : -1;
});
$.each(collection,function(i,el) {
    var color = this.className,
        $el = $(el);
    $el.css({backgroundColor: color}).appendTo( $el.parent() );
});

Answer 2

This example assumes you have to work with elements already on a page with classes assigned to them:

var classes = [];

// Populate classes array
// e.g., ["yellow", "red", "green", "blue", "pink", "orange", "black", "white"]
$('div.container').children().each(function (i, v) {
    classes.push(v.className);
});

// Assign random color to each div
$('div.container').children().each(function (i, v) {
    var color = Math.floor(Math.random()*classes.length)
    $(v).css({backgroundColor: classes.splice(color,1)});
});

http://jsfiddle.net/UgX3u/40/

Answer 3

var $container = $("div.container");
$container.html(shuffle($container.children().get()));

function shuffle(o){
    for(var j, x, i = o.length; i; j = parseInt(Math.random() * i), x = o[--i], o[i] = o[j], o[j] = x);
    return o;
};

Shuffle function found here

Updated: jsFiddle