JavaScript模块模式公共变量未更新

我使用的是带显示模块模式的角度服务。该服务从web服务内部提取字符串资源，并通过“Strings”公共变量使其可用。我必须初始化私有“strings”变量，因为它在服务调用之前被引用

我从服务获取正确的字符串数据，并将其复制到私有“strings”变量。但是，当客户端引用公共“字符串”时，它仍然保留其原始值

你知道我做错了什么，或者如何更新公共“字符串”吗

'use strict';

io1App.factory('Resources', ['$rootScope', 'DataService', '$q',
function ($rootScope, DataService, $q) {

   var urlBase = '/api/sfc/resource';

    // Need to pre-define 'ERROR_HEADER', since it is referenced in Index.html...before we have a chance to download it from the server.
   var strings = {
       'ERROR_HEADER': 'Error!'
   };

    var getStringResources = function (locale) {

        var url = urlBase + '/' + locale;

        var deferred = $q.defer();

        var promise = DataService.GetMethod(url);

        // Note that DataService.GetMethod(...) is returning a $q promise
        promise.then(function (data) {
            strings = data;
            deferred.resolve();
        },
        function (err) {
            deferred.reject(err);
        });

        return deferred.promise;
    };

    return {
        Strings: strings,
        GetStringResources: getStringResources
    }
}]);

服务调用将返回的数据设置为私有“strings”变量

promise.then(function (data) {
            strings = data;
            deferred.resolve();
        },

私有“字符串”现在显示以下内容（通过Chrome开发者工具）：

然而，当在角度控制器中引用公共“字符串”时，“字符串”仍然引用私有“字符串”的原始值

资源.字符串：

{
   'ERROR_HEADER': 'Error!'
};

---

有什么建议吗？

您正在将

字符串

变量完全替换为

数据

。它们是不同的对象，具有不同的引用，因此任何引用了以前的

字符串的客户端代码都不会看到更改

您可以扩充现有的
字符串
对象，而不是替换

promise.then(function (data) {
    // Merge properties into `strings`
    // You could also use any other "extension" technique, e.g. _.extend()
    for (var k in data) {
        if (data.hasOwnProperty(k)) {
            strings[k] = data[k];
        }
    }
    deferred.resolve();
},

从工厂方法返回的JavaScript对象永远不会用新的字符串对象更新。您需要保留对它的引用才能更新“公共视图”：

然后更新
。然后
回调以更新私有变量和公共服务对象：

.then(function(data) {
    strings = service.strings = data;
    deferred.resolve(data); // don't need to resolve this with the strings, but why not?
}, function error(){...});

但是，由于您不再真正拥有“私有数据”（仅对公共变量的私有引用），因此您根本不需要拥有私有字符串变量：

io1App.factory('Resources', ['$rootScope', 'DataService', '$q',
function ($rootScope, DataService, $q) {

    var urlBase = '/api/sfc/resource';

    var service = {
        // Need to pre-define 'ERROR_HEADER', since it is referenced in Index.html...before we have a chance to download it from the server.
        Strings: { 'ERROR_HEADER': 'Error!' },
        GetStringResources: function (locale) {
            var url = urlBase + '/' + locale;
            var deferred = $q.defer();
            var promise = DataService.GetMethod(url);

            // Note that DataService.GetMethod(...) is returning a $q promise
            promise.then(function (data) {
                service.strings = data;
                deferred.resolve(data); // don't need to resolve this with the strings, but why not?
            },
        function (err) {
            deferred.reject(err);
        });

        return deferred.promise;
    };
    return service;
}]);

谢谢voithos…这确实解决了问题。我一直在以类似的方式使用存储库，并没有遇到这种明显的参考与价值问题…我需要更多地了解这一点。谢谢squid314…有趣…我也会尝试这种方法。没问题。正如@voithos所说，这是一个参考与价值的问题。基本上，您有两个指向同一个值的指针（或引用），您只将其中的一个更新为新值（特别是私有值）。
.then(function(data) {
    strings = service.strings = data;
    deferred.resolve(data); // don't need to resolve this with the strings, but why not?
}, function error(){...});

io1App.factory('Resources', ['$rootScope', 'DataService', '$q',
function ($rootScope, DataService, $q) {

    var urlBase = '/api/sfc/resource';

    var service = {
        // Need to pre-define 'ERROR_HEADER', since it is referenced in Index.html...before we have a chance to download it from the server.
        Strings: { 'ERROR_HEADER': 'Error!' },
        GetStringResources: function (locale) {
            var url = urlBase + '/' + locale;
            var deferred = $q.defer();
            var promise = DataService.GetMethod(url);

            // Note that DataService.GetMethod(...) is returning a $q promise
            promise.then(function (data) {
                service.strings = data;
                deferred.resolve(data); // don't need to resolve this with the strings, but why not?
            },
        function (err) {
            deferred.reject(err);
        });

        return deferred.promise;
    };
    return service;
}]);