javascript - KnockoutJS - 嵌套 JSON 对象

Question

我正在尝试扩展我对 KnockoutJS 的知识(我有较高的理解)。我正在使用 Web API 构建一个 C# 项目来处理数据访问 -> 表示层，但是我的 View 模型遇到了一些问题，而且我确实知道这是我做错的事情，所以希望有人可以帮助我并解释我做了什么？

我们将从数据库中获取“类(class)”，并以 JSON 格式返回。这是类(class):

类(class).cs

using System;

namespace TestApplication.Model
{
    public class Lesson
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public virtual Teacher Teacher { get; set; }
        public virtual Classroom Classroom { get; set; }
        public virtual Subject Subject { get; set; }
        public virtual DateTime StartTime { get; set; }
        public virtual DateTime EndTime { get; set; }
    }
}

如果我直接进入 Web API 路线，这是返回的类(class):

Lessons.JSON

[  
 {  
  "id":1,
  "name":"Lesson 1",
  "teacher":{  
     "id":3,
     "firstName":"Sophie",
     "lastName":"Adams",
     "emailAddress":"teacher3@foo.com"
  },
  "classroom":{  
     "id":1,
     "name":"Great Hall"
  },
  "subject":{  
     "id":4,
     "name":"jQuery"
  },
  "startTime":"2016-02-10T09:30:00",
  "endTime":"2016-02-10T10:30:00"
},
{  
  "id":2,
  "name":"Lesson 2",
  "teacher":{  
     "id":4,
     "firstName":"Tristan",
     "lastName":"Sanchez",
     "emailAddress":"teacher4@foo.com"
  },
  "classroom":{  
     "id":2,
     "name":"Room 1A"
  },
  "subject":{  
     "id":3,
     "name":"SQL"
  },
   "startTime":"2016-02-10T09:00:00",
  "endTime":"2016-02-10T10:30:00"
}
]

最后，这是我的 KnockoutModel:

LessonsViewModel.js

var lessonRegisterViewModel;

function Lesson(id, name, teacher, room, subject, startTime, endTime) {
    var self = this;
    self.Id = ko.observable(id);
    self.Name = ko.observable(name);
    self.Teacher = ko.observable(teacher);
    self.Room = ko.observable(room);
    self.Subject = ko.observable(subject);
    self.StartTime = ko.observable(startTime);
    self.EndTime = ko.observable(endTime);
    self.addLesson = function() {
        var dataObject = ko.toJSON(this);
        $.ajax({
            url: '/api/Lessons',
            type: 'post',
            data: dataObject,
            contentType: 'application/json',
            success: function(data) {
                lessonRegisterViewModel.lessonListViewModel.lessons.push(new Lesson(data.Id, data.Name, data.Teacher, data.Room, data.Subject, data.StartTime, data.EndTime));
                self.Id(null);
                self.Name('');
                self.Teacher('');
                self.Room('');
                self.Subject('');
                self.StartTime('');
                self.EndTime('');
            }
        });
    }
}

function LessonList() {
    var self = this;
    self.lessons = ko.observableArray([]);
    self.getLessons = function() {
        self.lessons.removeAll();
        $.getJSON('/api/Lessons', function(data) {
            $.each(data, function(key, value) {
                self.lessons.push(new Lesson(value.id, value.name, value.teacher, value.room, value.subject, value.startTime, value.endTime));
                console.log(self);
            });
        });
    };
    self.removeLesson = function(lesson) {
        $.ajax({
            url: '/api/Lessons/' + lesson.Id(),
            type: 'delete',
            contentType: 'application/json',
            success: function() {
                self.lessons.remove(lesson);
            }
        });
    }
}
lessonRegisterViewModel = {
    addLessonViewModel: new Lesson(),
    lessonListViewModel: new LessonList()
};
$(document).ready(function() {
    // bind view model to referring view
    ko.applyBindings(lessonRegisterViewModel);
    // load lesson data
    lessonRegisterViewModel.lessonListViewModel.getLessons();
});

类(class)数量、名称、开始和结束时间的绑定(bind)工作正常，这只是嵌套对象，以及如何映射这些对象以从这些类中获取我需要的值是这里的痛苦，但任何一般性改进/建设性批评也很受欢迎。

Answer 1

您可以为嵌套对象定义单独的模型:

function Lesson(id, name, teacher, room, subject, startTime, endTime) {
    var self = this;
    self.Id = ko.observable(id);
    self.Name = ko.observable(name);
    self.Teacher = new Teacher(teacher);
    self.Room = new Classroom(room);
    self.Subject = new Subject(subject);
    self.StartTime = ko.observable(startTime);
    self.EndTime = ko.observable(endTime);

    //....
}

function Teacher(t) {
    var self = this;
    self.Id = ko.observable(t.id);
    self.FirstName = ko.observable(t.firstName);
    self.LastName = ko.observable(t.lastName);
    self.EmailAddress = ko.observable(t.emailAddress);
}

function Classroom(c) {
    var self = this;
    self.Id = ko.observable(c.id);
    self.Name = ko.observable(c.name);
}

function Subject(s) {
    var self = this;
    self.Id = ko.observable(s.id);
    self.Name = ko.observable(s.name);
}