问jQuery按列表内容日期或字母顺序对列表进行排序

EN

<select id="test">
    <option selected="selected" value="date">Date</option>
    <option value="alphabetically">Alphabetically</option>
</select>
<ul id="list">
  <li><p class="name">Peter</p><span class="date">10.12.12</span></li>
  <li><p class="name">Mary</p><span class="date">06.01.13</span></li>
  <li><p class="name">Paul</p><span class="date">19.12.12</span></li>
  <li><p class="name">Allen</p><span class="date">21.12.12</span></li>
  <li><p class="name">James</p><span class="date">03.01.13</span></li>
  <li><p class="name">Vicki</p><span class="date">12.01.13</span></li>
  <li><p class="name">Brock</p><span class="date">01.01.13</span></li>
  <li><p class="name">Dana</p><span class="date">31.12.12</span></li>
  <li><p class="name">Frank</p><span class="date">16.12.12</span></li>
  <li><p class="name">Gil</p><span class="date">09.01.13</span></li>
  <li><p class="name">Helen</p><span class="date">14.01.13</span></li>
</ul>

function sortUnorderedList(ul, sortDescending) {
  if (typeof ul == "string") ul = document.getElementById(ul);
  var lis = ul.getElementsByTagName("li");
  var vals = [];
  for (var i = 0, l = lis.length; i < l; i++)
  vals.push(lis[i].innerHTML);
  vals.sort();
  if (sortDescending) vals.reverse();
  for (var i = 0, l = lis.length; i < l; i++)
  lis[i].innerHTML = vals[i];
}
$(document).ready(function () {
  var desc = false;
  document.getElementById("test").onchange = function () {
    sortUnorderedList("list", desc);
    desc = !desc;
    return false;
  };
});
function sortDescending(a, b) {
  var date1 = $(a).find(".date").text();
  date1 = date1.split('.');
  date1 = new Date(date1[2], date1[1] - 1, date1[0]);
  var date2 = $(b).find(".date").text();
  date2 = date2.split('.');
  date2 = new Date(date2[2], date2[1] - 1, date2[0]);
  return date1 < date2 ? 1 : -1;
}
$(document).ready(function () {
  $('ul > li').sort(sortDescending).appendTo('ul');
});