怎样获取ng-change事件的当前元素

Question

angular中操作dom元素，ng-click可通过 $event获取

<input id="dd" type="text" class="form-control"
           ng-click="showMenu($event)" ng-model="dept.name" readonly>、

scope.showMenu = function (event) {
    console.log($(event.target).attr('id'));                                            
    $(event.target).next().css({left:15+'px', top:34+'px',display: 
    "block"}).slideDown("fast");                                                                 
}

ng-change怎么获取？