Ajax的应用在平时的工作中，很是常见，这篇文章，完全是为了，巩固复习。

我们先看看不使用json格式返回分部视图：

先说需求吧：

我有两个实体，一个是出版商【Publisher】，一个是书【Book】（很显然这是一对多的关系，一个出版商可以出版很多书籍，一本书只有一个出版商。），这里，我要实现的是，在出版商页面，使用DropDownList加载出来有哪些出版商，然后选择出版商的时候，异步加载分部视图，加载这个出版商出版的书籍的数据。

打算使用EF来做，也当是一个复习吧：

1.首先新建一个空白的MVC web项目：，在Model文件夹下面新建两个实体：

BOOK实体：

using System; using System.Collections.Generic; using System.Linq; using System.Web; namespace AjaxDataInMVC.Models { public class Book { public int BookID { get; set; } public string Title { get; set; } public string Auther { get; set; } public string Price { get; set; } public string Year { get; set; } public int PublisherID { get; set; } public virtual Publisher Publisher { get; set; } } }

Book

Punlisher实体：

using System; using System.Collections.Generic; using System.Linq; using System.Web; namespace AjaxDataInMVC.Models { public class Publisher { /// <summary> /// 出版编号 /// </summary> public int PublisherID { get; set; } /// <summary> /// 出版商名称 /// </summary> public string PublisherName { get; set; } /// <summary> /// 出版日期 /// </summary> public string PublisherYear { get; set; } public virtual ICollection<Book> Books { get; set; } } }

Publisher

2.接着，添加EF引用，然后在根目录下，新建一个Map文件夹，在里面新建两个实体：

using AjaxDataInMVC.Models; using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations.Schema; using System.Data.Entity.ModelConfiguration; using System.Linq; using System.Web; namespace AjaxDataInMVC.Map { public class BookMap:EntityTypeConfiguration<Book> { public BookMap() { //设置主键 this.HasKey(x => x.BookID); this.Property(x => x.BookID).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity); this.Property(x => x.Price).IsRequired(); this.Property(x => x.Auther).IsRequired().HasMaxLength(50); this.Property(x => x.Title); this.Property(x => x.Year); this.HasRequired(x => x.Publisher).WithMany(x => x.Books).HasForeignKey(x => x.PublisherID).WillCascadeOnDelete(true); this.ToTable("Books"); } } }

BookMap

using AjaxDataInMVC.Models; using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations.Schema; using System.Data.Entity.ModelConfiguration; using System.Linq; using System.Web; namespace AjaxDataInMVC.Map { public class PublisherMap:EntityTypeConfiguration<Publisher> { public PublisherMap() { //主键 this.HasKey(x => x.PublisherID); this.Property(x => x.PublisherID).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity); this.Property(x => x.PublisherName).HasMaxLength(50).IsRequired(); this.Property(x => x.PublisherYear).IsRequired(); this.ToTable("Publishers"); } } }

PublisherMap

3.现在就是新建数据上下文类了，在Map文件夹下：

using System; using System.Collections.Generic; using System.Data.Entity; using System.Data.Entity.ModelConfiguration; using System.Linq; using System.Reflection; using System.Web; namespace AjaxDataInMVC.Map { public class MyDbContext:DbContext { public MyDbContext() : base("name=DbConnectionString") { } protected override void OnModelCreating(DbModelBuilder modelBuilder) { var typesToRegister = Assembly.GetExecutingAssembly().GetTypes() .Where(type => !String.IsNullOrEmpty(type.Namespace)) .Where(type => type.BaseType != null && type.BaseType.IsGenericType && type.BaseType.GetGenericTypeDefinition() == typeof(EntityTypeConfiguration<>)); foreach (var type in typesToRegister) { dynamic configurationInstance = Activator.CreateInstance(type); modelBuilder.Configurations.Add(configurationInstance); } // base.OnModelCreating(modelBuilder); } } }

MyDbContext

别忘了，配置文件中加上：

<connectionStrings> <add connectionString="server=.;database=MyBookDB;uid=sa;pwd=Password_1" providerName="System.Data.SqlClient"/> </connectionStrings>

5.这里特别提到，创建下拉框，我们可以新建一个ViewModel性质的实体

using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations; using System.Linq; using System.Web; using System.Web.Mvc; namespace AjaxDataInMVC.ViewModel { public class PublisherViewModel { public PublisherViewModel() { PublisherList = new List<SelectListItem>(); } [Display(Name="PublishName")] public int PublisherID { get; set; } public IEnumerable<SelectListItem> PublisherList { get; set; } } }

 4.创建对应的控制器：

using AjaxDataInMVC.Map; using AjaxDataInMVC.Models; using AjaxDataInMVC.ViewModel; using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.Mvc; namespace AjaxDataInMVC.Controllers { public class PublisherController : Controller { private MyDbContext context; public PublisherController() { context = new MyDbContext();
　　　　　　　　//检测到循环引用可以加上这句 context.Configuration.ProxyCreationEnabled = false; } // GET: Publisher public ActionResult Index() { List<Publisher> lstPublisher = context.Set<Publisher>().ToList(); PublisherViewModel model = new PublisherViewModel(); model.PublisherList = lstPublisher.Select(x => new SelectListItem() { Text = x.PublisherName, Value = () }); return View(model); } } }