javascript - 调用服务返回未定义

Question

我正在创建一个名为 ActiveUserProfileService 的服务，但是当我在 Controller 中调用它的函数时，我得到了 undefined 并且我无法弄清楚为什么。最奇怪的是，在 ActiveUserProfileService 服务中，来自 UserService 的信息是通过 console.log 显示的，所以我正在接收信息，但是在调用 code>ActiveUserProfileService 在 Controller 中，它给我 undifened。似乎数据没有传递。有人可以帮助我吗？

用户服务.js:

(function () {
    'use strict';

    angular
        .module('myApp')
        .factory('UserService', UserService);

    UserService.$inject = ['$http'];

    /* @ngInject */
    function UserService($http) {
        var service = {
            getAuthenticatedUser:         getAuthenticatedUser,
            getUserInformation:           getUserInformation

        };
        return service;

        function getUserInformation(idUser) {
            return $http.post('api/user/details', {idUser: idUser});
        }
        function getAuthenticatedUser() {
            return $http.get('api/user');
        }

    }

})();

ActiveUserProfileService.js

(function () {
    'use strict';

    angular
        .module('myApp')
        .factory('ActiveUserProfileService', ActiveUserProfileService);

    ActiveUserProfileService.$inject = ['$http','UserService'];

    /* @ngInject */
    function ActiveUserProfileService($http, UserService) {


        var service = {
            isAccount:            isAccount
        };
        return service;

        ////////////////

        function isAccount(accountName) {
            UserService.getAuthenticatedUser()
                .then(function (response) {
                    var data = response.data;

                    UserService.getUserInformation(data.user.id)
                        .then(function (response) {
                            var userDetails = response.data;
                            console.log("It is");
                            console.log(accountName == userDetails.account_types[0].description_internal);

                            return  accountName == userDetails.account_types[0].description_internal;
                        });
                })
        }

    }

})();

我的 Controller :

(function () {
    'use strict';

    angular
        .module('myApp')
        .controller('WizardController', WizardController);

    WizardController.$inject = [
        'UserService',

        'ActiveUserProfileService'

    ];

    /* @ngInject */
    function WizardController(UserService,ActiveUserProfileService) {

        var vm = this;


       console.log("ActiveUserProfileService");
    console.log(ActiveUserProfileService.isAccount("professional")); //is Returning me undefined



    }

})
();

Answer 1

重点是，您正试图在另一个回调函数中为 isAccount 返回一个值。当您这样做时，您将向此函数返回一个值，而不是 isAccount 本身，因此 isAccount 将不会返回任何未定义的内容。由于您正在调用异步方法，因此 isAccount 也必须是异步的，

替换

 function isAccount(accountName) {
        UserService.getAuthenticatedUser()
            .then(function (response) {
                var data = response.data;

                UserService.getUserInformation(data.user.id)
                    .then(function (response) {
                        var userDetails = response.data;
                        console.log("It is");
                        console.log(accountName == userDetails.account_types[0].description_internal);

                        return  accountName == userDetails.account_types[0].description_internal;
                    });
            })
    }

与

 function isAccount(accountName) {
    var deferred = $q.defer();
        UserService.getAuthenticatedUser()
            .then(function (response) {
                var data = response.data;
                //when the user is loaded, then you resolve the promise you has already returned
                UserService.getUserInformation(data.user.id)
                    .then(function (response) {
                        var userDetails = response.data;
                        console.log("It is");
                        console.log(accountName == userDetails.account_types[0].description_internal);
                        deferred.resolve(accountName == userDetails.account_types[0].description_internal);
                        return; //here is not isAccount return, but anonymous inner function 'function (response)', you got it?
                    });
            });
    return deferred.promise; //return as soon as creates the promise
}

当然你也必须注入(inject) $q 服务