<div ng-app="TestApp">

        <div ng-controller="TestAppCtrl">

            <label>options变化之后会出错：</label>

            <select ng-model="selectedSite">

                <option  value="" >---请选择---</option>

                <option ng-repeat="site in sites" value="{{site.url}}">{{site.name}}</option>

            </select>

            <input type="button" ng-click="reload()" value="更新">

        </div>

    <div>

        var testApp = angular.module('TestApp', []);

        testApp.controller('TestAppCtrl', ['$scope',

        function($scope) {

            var sites=[{"url":"http://www.baidu.com","name":"百度"},

                       {"url":"http://www.google.com","name":"谷歌"},

                       {"url":"http://www.yahoo.com","name":"雅虎"},

                        ]

            var sites2=[{"url":"http://www.gmail.com","name":"GMAIL"},

                       {"url":"http://www.abc.com","name":"ABC"},

                       {"url":"http://www.xyz.com","name":"XYZ"},

                        ]

            var Init = function(){

                $scope.sites=sites;

            }

            var Reload = function(){

                $scope.sites=sites2;

            }

　　　　　　　//加载页面之后初始化
            Init();
　　　　　　　//注册更新按钮的点击事件，点击之后更新select的option列表

            $scope.reload=Reload;

            }]

        );

    <div ng-app="TestApp">

        <div ng-controller="CorrectedAppCtrl">

            <label>正确写法：</label>

            <select ng-model="selectedSite" ng-options="site as site.name for site in sites track by site.url">

                <option  value="" >---请选择---</option>

            </select>

            <input type="button" ng-click="reload()" value="更新">

        </div>

    <div>