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前端使用AngularJS的$resource,后端ASP.NET Web API，实现增删改查
AngularJS中的$resource服务相比$http服务更适合与RESTful服务进行交互。本篇后端使用ASP.NET Web API, 前端使用$resource，实现增删改查。
领域和上下文
首先领域先行。
public class StudentVm{[Key]public int Id { get; set; }public string Name { get; set; }public string Age { get; set; }}
上下文。
public class StudentContext : DbContext{public StudentContext() : base("conn"){Database.SetInitializer(new StudentInitializer());}public DbSet<StudentVm> Students { get; set; }}
上下文的构造函数中，StudentIntializer类对数据进行了初始化。
public class StudentInitializer : CreateDatabaseIfNotExists<StudentContext>{protected override void Seed(StudentContext context){IList<StudentVm> students = new List<StudentVm>();students.Add(new StudentVm() { Name = "aa", Age = "20" });students.Add(new StudentVm() { Name = "bb", Age = "18" });students.Add(new StudentVm() { Name = "cc", Age = "22" });students.Add(new StudentVm() { Name = "dd", Age = "23" });students.Add(new StudentVm() { Name = "ee", Age = "20" });students.Add(new StudentVm() { Name = "ff", Age = "21" });students.Add(new StudentVm() { Name = "gg", Age = "28" });foreach(StudentVm student in students){context.Students.Add(student);}base.Seed(context);}}
对于EF Code First来说，Web.config中需要配置连接字符串。
<connectionStrings><add name="conn"connectionString="Data Source=.;User=yourname;Password=yourpassword;Initial Catalog=StudentsDemo;Integrated Security=True"providerName="System.Data.SqlClient"/></connectionStrings>
Repository
在这里使用上下文类，实现增删改查。
public class StudentsReop{private StudentContext _db = new StudentContext();public IEnumerable<StudentVm> Query(){return _db.Students;}public StudentVm Get(int id){return _db.Students.SingleOrDefault(s => s.Id == id);}//更新public void Put(int id, StudentVm student){var stu = _db.Students.SingleOrDefault(s => s.Id == id);_db.Students.Attach(stu);_db.Entry(stu).State = System.Data.Entity.EntityState.Modified;_db.Entry(stu).CurrentValues.SetValues(student);_db.SaveChanges();}//添加public void Post(StudentVm student){_db.Students.Add(student);_db.SaveChanges();}public void Delete(int id){var student = _db.Students.SingleOrDefault(s => s.Id.Equals(id));_db.Students.Remove(student);bool saveFailed;do{saveFailed = false;try{_db.SaveChanges();}catch (DbUpdateConcurrencyException ex){saveFailed = true;//重新加载数据库中的实体，使之处于unchanged的状态ex.Entries.Single().Reload();}} while (saveFailed);}}
API控制器
public class StudentsController : ApiController{private StudentsReop _reop = new StudentsReop();//GET api/Studentspublic HttpResponseMessage Get(){var students = _reop.Query().ToList();return Request.CreateResponse(HttpStatusCode.OK, students);}//GET api/Students/5public HttpResponseMessage Get(int id){var student = _reop.Get(id);return Request.CreateResponse(HttpStatusCode.OK, student);}//POST api/Studentspublic void Post([FromBody]StudentVm student){_reop.Post(student);}//PUT api/Students/5public void Put(int id, [FromBody]StudentVm student){_reop.Put(id, student);}//DELETE api/Studentspublic void Delete(int id){_reop.Delete(id);}}
允许跨域访问
默认情况下，ASP.NET Web API是不支持跨域访问的。为了支持，需要安装Microsoft.AspNet.WebApi.Cors。安装之后，需要在全局配置生效。在WepApiConfig.cs中配置如下：
public static class WebApiConfig{public static void Register(HttpConfiguration config){// Web API 配置和服务// Web API 路由config.MapHttpAttributeRoutes();config.EnableCors(new EnableCorsAttribute("*", "*", "*"));config.Routes.MapHttpRoute(name: "DefaultApi",routeTemplate: "api/{controller}/{id}",defaults: new { id = RouteParameter.Optional });}}
在本地，浏览器中：http://localhost:49621/api/Students
前端准备
后端完成，前端在WebStorm下安装先安装需要的几个插件：
npm install angular
npm install angular-route
npm install angular-resource
npm install angular-cookies
npm install alertify
再来了解下前端的文件结构：
app.js 主module，路由都在这里配置
index.html 主视图，引用所有的css,js文件，提供让其它部分视图呈现的一块区域<div ng-view></div>
.....service/ 自定义服务，$resouce的核心就封装在这里
..........studentService.js
.....controller/
..........studentsCtrl.js 列表
..........studentUpdateCtrl.js 更新
..........studentCreateCtrl.js 添加
.....views/
..........Students.html 列表
..........StudentInfo.html 更新
..........StudentCreate.html 添加
index.html
<!DOCTYPE html>
<html lang="en" ng-app="studentManagement">
<head><meta charset="UTF-8"><title>{{title}}</title><link rel="stylesheet" href="node_modules/alertify/themes/alertify.core.css"/>
</head>
<body><div><p><a href="#/">Students</a> <a href="#/Create">Create Student</a></p></div><div ng-view></div><script src="node_modules/angular/angular.min.js"></script><script src="node_modules/angular-route/angular-route.min.js"></script><script src="node_modules/angular-resource/angular-resource.min.js"></script><script src="node_modules/angular-cookies/angular-cookies.min.js"></script><script src="node_modules/alertify/lib/alertify.min.js"></script><script src="app.js"></script><script src="service/studentService.js"></script><script src="controller/studentUpdateCtrl.js"></script><script src="controller/studentsCtrl.js"></script><script src="controller/studentCreateCtrl.js"></script></body>
</html>
以上，主视图中，需要注意引用js文件的顺序，一般angualr相关方在最上面，然后app对应js文件，最后是各种服务和控制器相关js文件。
app.js
在这里，当然首先要定义一个module，定义module的时候要把所有用到的module依赖写在module方法的第二个实参里。还有一个主项工作就是定义设置路由，而且，如果想让以后视同从controller中拿数据更快，我们还可以利用路由的resolve机制，把数据从某处读取出来，先放到路由中，然后在controller中把resolve机制下的数据读出来。
"use strict";var studentsManagement = angular.module("studentManagement",["ngResource","ngCookies","ngRoute"]).run(function($rootScope){$rootScope.title = "Home";}).config(["$routeProvider","$locationProvider", function($routeProvider, $locationProvider){//关于url的基本配置//$locationProvider.html5Mode({// enabled: true,// requireBase: false//});//配置路由$routeProvider.when("/", {templateUrl: "views/Students.html",controller: "studentsCtrl",resolve: {students: function($q,studentDataService){//$q异步执行方法var deferred = $q.defer();studentDataService.query(function(data){deferred.resolve(data);});return deferred.promise;}}}).when("/Student/:id",{templateUrl: "views/StudentInfo.html",controller: "studentUpdateCtrl",resolve: {student: function($q, studentDataService, $route){var defered = $q.defer();//从路由中获取id的值var id = $route.current.params.id;studentDataService.get({id: id}, function(data){defered.resolve(data);});return defered.promise;}}}).when("/Create",{templateUrl: "views/CreateStudent.html",controller: "studentCreateCtrl"});}]);
● 使用$routeProvider配置路由的过程就是让一对对view和controller结婚的过程
● 显示列表的时候通过路由的resolve机制把数据先放在了路由中
● 显示某个Sudent的时候也通过路由的resolve机制把数据先放在了路由中
●/Student/:id这个路由格式中的id代表变量，可借助$route服务从路由中取出来var id = $route.current.params.id;
studentService.js
在这里，封装了对API的所有请求。
而$resource服务是位于angular-resource中，大致按如下调用：
$resource(url,{paramDefaults},{actions},{options});
其中，第一个参数是必须的，其它都optional。
angular.module('studentManagement').factory("studentDataService",["$resource", function($resource){var baseUrl = "http://localhost:49621/api/Students";return $resource("http://localhost:49621/api/Students",{},{query: {method: "GET", isArray: true },create: {method: "POST"},get: {method: "GET", url: baseUrl + "?id=:id"},remove: {method: "DELETE", url: baseUrl + "?id=:id"},update: {method: "PUT", url: baseUrl + "?id=:id"}})
}]);
以上，在"?id=:id"中，冒号后面的id是一个变量，在controller中通过对象传递到这里来，比如studentDataService.remove({id: id}).$promise.then(...)
列表，studentsCtr.j和views/Students.html这对恋人
studentsCtr.js：
angular.module('studentManagement').controller("studentsCtrl",['$scope','$route','$rootScope','studentDataService', function($scope,$route, $rootScope, studentDataService){$rootScope.title = "Students";$scope.students = $route.current.locals.students;//students在路由resolve中定义$scope.removeStudent = function(id, student){studentDataService.remove({id: id}).$promise.then(function(){//获取student在当前集合中的索引var index = $scope.students.indexOf(student);$scope.students.splice(index, 1);alertify.log(student.Name + ' is removed');});};}]);
以上，students的数据并没有向那个源头发出请求获取，而是直接使用$route服务，把路由resolve机制中的变量值取了出来。删除数据实际是做2件事，一件是删除服务端的数据，一件是删除model中的数据。
Students.html:
<table><thead><tr><th>Name</th><th>Age</th><th>Actions</th></tr></thead><tbody><tr ng-repeat="student in students"><td>{{student.Name}}</td><td>{{student.Age}}</td><td><a href="#/Student/{{student.Id}}">更新</a> <a href="javascript:void(0)" ng-click="$parent.removeStudent(student.Id, student)">移除</a></td></tr></tbody>
</table>
添加，studentCreateCtrl.js和views/CreateStudent.html这对恋人
studentCreateCtrl.js：
angular.module('studentManagement').controller("studentCreateCtrl", ["$scope", "studentDataService", '$rootScope', "$location", function ($scope, studentDataService, $rootScope, $location) {$rootScope.title = "Create student";$scope.saveStudent = function (student) {studentDataService.create(student).$promise.then(function (res) {$location.path('/');});};
}]);
CreateStudent.html：
<form><input id="userName" ng-model="student.Name" /><br/><input id="userAge" ng-model="student.Age" /><br/><button ng-click="saveStudent(student)">Save</button><button type="reset">Cancel</button> </form>
更新，studentUpdateCtrl.js和views/StudentInfo.html这对恋人
studentUpdateCtrl.js：
angular.module('studentManagement').controller("studentUpdateCtrl",["$scope","$route","$rootScope","studentDataService","$location", function($scope,$route, $rootScope, studentDataService, $location){//student是在resolve中定义的$scope.student = $route.current.locals.student;$rootScope.title = "Student Info -" + $scope.student.Name;$scope.updateInfo = function(student){studentDataService.update({id: student.Id}, student).$promise.then(function(){$location.url("/");alertify.log("Updated Student Scucess");});};
}]);
StudentInfo.html：
<form><input type="text" id="userName" ng-model="student.Name"/><br/><input type="text" id="userAge" ng-model="student.Age"/><br/><button ng-click="updateInfo(student)">Update</button><button type="reset">Reset</button> </form>