按键操作

1. 按键不操作0.5秒后执行某个函数：
   

   <input class="form-control" ng-model="$ctrl.data.keyword" placeholder="please input site.."
                          style="border-right: 0;"
                          ng-change="$ctrl.searchSite()" ng-model-options="{debounce: 500}"/>

2. 回车按键搜索：
   

   ng-keyup="$ctrl.keySearch($event)"

   
   $scope.keySearch = function (e) {
               var keycode = window.event ? e.keyCode : e.which;
               if (keycode == 13) {
                   $scope.search(data.keyword);
               }
           };
   

3. 上下键来回切换列表选择：