angular实现select的ng-options4

<div ng-controller="ngSelect">
<select ng-model="vm.selectVal" ng-options="o.title for o in vm.optionsData">
<option value="">请选择</option>
</select>
</div>

var app = angular.module("app",[]);
app.controller("ngSelect",function($scope){

var vm = $scope.vm = {};

//数组对象用来给ng-options遍历
vm.optionsData = [{
title : "angularJs"
},{
title : "emberJs"
},{
title : "backboneJs"
},{
title : "knockoutJs"
}];

})

<select ng-model="vm.selectVal" ng-options="o.id as o.title for o in vm.optionsData" ng-change="selectChange()">
<option value="">请选择</option>
</select>

vm.optionsData = [{
id : 4543,
title : "angularJs"
},{
id : 546,
title : "emberJs"
},{
id : 456,
title : "backboneJs"
},{
id : 75,
title : "knockoutJs"
}];

$scope.selectChange = function(){
//添加了ng-change事件来试试id值的输出
console.log(vm.selectVal);
}