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我需要在 Javascript 中创建智能对象/函数以与我的 AngularJS 应用程序一起使用。我应该为此使用什么模式？我目前正在使用我研究过的通用 JavaScript“模块”模式，但我想知道是否应该以 AngularJS 方式对这些对象/函数（如下）进行建模。也许作为“服务”？

我来自 Java 背景，这让我有点不舒服将带有辅助方法的对象称为“服务”。但我可能需要调整我对 JavaScript/AngularJS 的定义。

该应用程序是一个基本的评分系统。两个主要对象/功能如下：

课程记分卡

/* 
 * LessonScoreCard
 * 
 * Is a "module" that keeps track of the score a user has for a given lesson
 * and whether or not for a given question there are more correct answers 
 * that can be made.
 */

var lessonScoreCard = (function() {

    //Map of questions to scores
    var privateQuestionNumberToScoreMap = {};

    //API to be used by external clients
    var publicAPI = {

        //A public function utilizing privates
        setScore: function(questionNumber, score) {
            privateQuestionNumberToScoreMap[ questionNumber ] = score;
        },

        //Sum the total score
        getTotalScore: function( ){
            var totalScore = 0;
            for( var questionNumber in privateQuestionNumberToScoreMap ){
                totalScore += privateQuestionNumberToScoreMap[questionNumber];
            }
        }
    };

    return publicAPI;
})();

答案键

/* 
 * AnswerKey
 * 
 * Is a "module" that takes an answer key and performs functions
 * related to it.
 */

var answerKey = (function() {

    //Set of right answers
    var privateQuestionNumberToAnswerArrayMap;

    //API to be used by external clients
    var publicAPI = {
        setAnswerKey: function(answerKeyModel) {
            privateQuestionNumberToAnswerArrayMap = answerKeyModel;
        },
        // A public function utilizing privates
        isCorrect: function(question, answer) {
            var isCorrect = false;

            var answerArray = privateQuestionNumberToAnswerArrayMap[ question ];
            if (answerArray.indexOf(answer) !== -1) {
                isCorrect = true;
            }
            return isCorrect;
        },

        getAnswerCount: function( question ){
            var answerArray = privateQuestionNumberToAnswerArrayMap[ question ];
            return answerArray.length;
        }

    };

    return publicAPI;

})();

示例 JSON 答案密钥模型 

    {
        1: [1, 3],
        2: [4]
    }
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1 回答 1

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aet is right, but I would expand the role of services even further. Services and directives are your two primary building blocks when constructing an app on top of Angular.

Directives are tightly coupled to the view. They are for:

  1. Changing some data in response to user input or action
  2. Updating the UI in response to a change in data

Services are very uncoupled from the view. They're for:

  1. Encapsulating business logic
  2. Storing more robust model data that you want to share throughout your app, especially if your app is so large that it has more than 1 controller, or if your model data is tightly coupled to a persistence mechanism (e.g. a Backbone model)

So services can really do or be anything, as long as that thing isn't view-related. I think you should write your lessonScoreCard and answerKey modules as service factories, and inject them into any directives which need access to their functionality.

于 2013-10-14T23:59:23.847 回答