1. 概述
主要运用的包含3个类：，，
2. Model：一组字段和相关的业务逻辑
1）概述
Ext.data.Model，代表应用实体（如电子商务应用包含Users, Products 和 Orders），即定义一组字段和相关的业务逻辑。
Model重要组成部分：
2）创建一个Model
此Model包含两个选项：fields和，
Ext.define('MyApp.model.Base', { extend: 'Ext.data.Model', fields: [{ name: 'id', type: 'int' }], schema: { namespace: 'MyApp.model', // generate auto entityName proxy: { // Ext.util.ObjectTemplate type: 'ajax', url: '{entityName}.json', reader: { type: 'json', rootProperty: '{entityName:lowercase}' } } }}); 说明：
①代理：
介于和之间，用于处理加载或保存Model数据，有两种类型：Client 和Server
Client Proxy：包含 和
Server Proxy：处理数据的封送，与远程服务器链接，包含, 和 .
②Schema：彼此间有关联的实体的集合
User.json
{ "success": "true", "user": [ { "id": 1, "name": "Philip J. Fry" }, { "id": 2, "name": "Hubert Farnsworth" }, { "id": 3, "name": "Turanga Leela" }, { "id": 4, "name": "Amy Wong" } ]} 3. Stores：一个集合的记录（模型派生类的实例）
var store = new Ext.data.Store ({ model: 'MyApp.model.User'});store.load({ callback:function(){ var first_name = this.first().get('name'); console.log(first_name); }}); 1）内联数据：Stores也可以在网上加载数据。在内部，存储将每一个我们所传递的对象转换成合适的模型类型的数据
new Ext.data.Store({ model: 'MyApp.model.User', data: [{ id: 1, name: "Philip J. Fry" },{ id: 2, name: "Hubert Farnsworth" },{ id: 3, name: "Turanga Leela" },{ id: 4, name: "Amy Wong" }]}); 2）排序和分组
new Ext.data.Store({ model: 'MyApp.model.User', sorters: ['name','id'], filters: { property: 'name', value : 'Philip J. Fry' }}); 4. Associations：Models可以通过他连接在一起
大部分应用依赖与多个Models，这些Models几乎相关联，如‘博客应用’需要Models：User和Post，一个user可以
有多个Posts，但一个Post只能有一个User去创建，即‘多对一’关系：
Ext.define('MyApp.model.User', { extend: 'MyApp.model.Base', fields: [{ name: 'name', type: 'string' }]});Ext.define('MyApp.model.Post', { extend: 'MyApp.model.Base', fields: [{ name: 'userId', reference: 'User', // the entityName for MyApp.model.User type: 'int' }, { name: 'title', type: 'string' }]}); 如果你想得到一个User的所有Posts，可以：
// Loads User with ID 1 and related posts and comments// using User's ProxyMyApp.model.User.load(1, { callback: function(user) { console.log('User: ' + user.get('name')); //Each User model has many Posts, which added the user.posts() function that we used //Calling user.posts() returns a Store configured with the Post model user.posts(function(posts){ posts.each(function(post) { console.log('Post: ' + post.get('title')); }); }); }}); 关联（Associations）不仅对加载数据有用，也可以用于创建新的数据记录
user.posts().add({ userId: 1, title: 'Post 10'});user.posts().sync(); //saves the new Post via its proxy //The “inverse” of the association also generates new methods on the Post model:MyApp.model.Post.load(1, { callback: function(post) { //getUser()是异步的，需要一个回调函数来获得用户实例 post.getUser(function(user) { console.log('Got user from post: ' + user.get('name')); }); }});MyApp.model.Post.load(2, { callback: function(post) { post.setUser(100); //setUser()简单地更新userId（或叫“外键”）并保存Post Model }}); 加载嵌套数据：当关联定义之后可以执行，如下面的服务器响应内容
//we can return all of the data in a single server response{ "success": true, "user": [{ "id": 1, "name": "Philip J. Fry", "posts": [{ "title": "Post 1" },{ "title": "Post 2" },{ "title": "Post 3" }] }]} 5. 验证：Validations
1）在User model 里面添加验证
Ext.define('MyApp.model.User', { extend: 'Ext.data.Model', fields: ..., validators: { name: [ 'presence', { type: 'length', min: 7 }, { type: 'exclusion', list: ['Bender'] } ] }}); 5中验证：Presence，Length，Format，Inclusion，Exclusion
// now lets try to create a new user with as many validation测试上面// errors as we canvar newUser = new MyApp.model.User({ id: 10, //出现错误：Length must be greater than 7 name: 'Bender'});// run some validation on the new user we just createdconsole.log('Is User valid?', newUser.isValid());//returns 'false' as there were validation errorsvar errors = newUser.getValidation(), error = errors.get('name');console.log("Error is: " + error); //newUser.isValid() 此时将返回truenewUser.set('name', 'Bender Bending Rodriguez');errors = newUser.getValidation();