<p ng-controller="loginCtrl">
    <pre>{{login.info}}</pre>
    <button ng-click="setvalue()">aaaa</button>
</p>

app.controller('loginCtrl', ['$scope', 'login', function($scope, login){

        $scope.login= login;
        $scope.setvalue = function(){
            login.setvalue('dddd')
        }
    }])

这个涉及到的是js基础知识，和angular没什么关系了。简单示例：

jsvar ret = {};
ret.info = {isIn:false};
var $scope = {};
$scope.info = ret.info;

//这里修改
ret.info = {isIn:true,xx:'xx'};
console.log(ret.info, $scope.info);// 结果是：Object {isIn: true, xx: "xx"} Object {isIn: false}