orderBy 是一个排序用的过滤器标签。它可以像 sort 函数那样支持一个排序函数，也可以简单地指定一个属性名进行操作：
<div ng-controller="TestCtrl">
{{ data | orderBy: 'age' }} <br />
{{ data | orderBy: '-age' }} <br />
{{ data | orderBy: '-age' | limitTo: 2 }} <br />
{{ data | orderBy: ['-age', 'name'] }} <br />
</div>
<script type="text/javascript">
var TestCtrl = function($scope){
$scope.data = [
{name: 'B', age: 4},
{name: 'A', age: 1},
{name: 'D', age: 3},
{name: 'C', age: 3},
];
}
angular.bootstrap(document.documentElement);
</script>