gistfile1.js

/*
 *
 * Copyright (c) 2006-2009 Sam Collett (http://www.texotela.co.uk)
 * Modified by Phil Schalm to allow custom sorting via a passed in function
 *
 */

$.fn.sortOptions = function(ascending)
{
	// get selected values first
	var sel = $(this).selectedValues();
	var a = typeof(ascending) == "undefined" ? true : !!ascending;
	this.each(
		function()
		{
			if(this.nodeName.toLowerCase() != "select") return;
			// get options
			var o = this.options;
			// get number of options
			var oL = o.length;
			// create an array for sorting
			var sA = [];
			// loop through options, adding to sort array
			for(var i = 0; i<oL; i++)
			{
				sA[i] = {
					v: o[i].value,
					t: o[i].text
				}
			}
			// sort items in array
			if (typeof(ascending) == "function") {
			  sA.sort(ascending);
			} else {
  			sA.sort(
  				function(o1, o2)
  				{
  					// option text is made lowercase for case insensitive sorting
  					o1t = o1.t.toLowerCase(), o2t = o2.t.toLowerCase();
  					// if options are the same, no sorting is needed
  					if(o1t == o2t) return 0;
  					if(a)
  					{
  						return o1t < o2t ? -1 : 1;
  					}
  					else
  					{
  						return o1t > o2t ? -1 : 1;
  					}
  				}
  			);
  		}
			// change the options to match the sort array
			for(var i = 0; i<oL; i++)
			{
				o[i].text = sA[i].t;
				o[i].value = sA[i].v;
			}
		}
	).selectOptions(sel, true); // select values, clearing existing ones
	return this;
};