或者：http://www.codeproject.com/Articles/640302/CRUD-Operations-Using-Entity-Framework-Code-Fi
系列目录：
- Relationship in Entity Framework Using Code First Approach With Fluent API【【使用EF Code-First方式和Fluent API来探讨EF中的关系】】
- Code First Migrations with Entity Framework【使用EF 做数据库迁移】
- CRUD Operations Using Entity Framework 5.0 Code First Approach in MVC【在MVC中使用EF 5.0做增删查改】
- CRUD Operations Using the Repository Pattern in MVC【在MVC中使用仓储模式，来做增删查改】
- CRUD Operations Using the Generic Repository Pattern and Unit of Work in MVC【在MVC中使用泛型仓储模式和工作单元来做增删查改】
- CRUD Operations Using the Generic Repository Pattern and Dependency Injection in MVC【在MVC中使用泛型仓储模式和依赖注入，来做增删查改】
本来不想写这篇的，因为感觉增删查改，实在是太Easy了。好了，为了巩固学习，还是继续吧：
打算实现书籍的增删查改，有两个实体，一个是Book【书籍实体】，另外一个是出版商实体【Publisher】，一个出版商可以出版很多书籍，一本书只能是由一个出版商出版。所以，书籍和出版商之间是一对多的关系。
先来看看整个项目的结构吧：
Entity实体中：
BaseEntity实体：【日期使用了数据注解，这样在显示的时候，就有格式了。】
using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations; using System.Linq; using System.Text; using System.Threading.Tasks; namespace EF.Entity { public abstract class BaseEntity { /// <summary>
/// ID /// </summary>
public int ID { get; set; } /// <summary>
/// 添加时间 /// </summary>
///
[DataType(DataType.Date)] [DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)] public DateTime AddedDate { get; set; } /// <summary>
/// 修改时间 /// </summary>
///
[DataType(DataType.Date)] [DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)] public DateTime ModifiedDate { get; set; } } }
Book实体：
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace EF.Entity { /// <summary>
/// Book实体 /// </summary>
public class Book:BaseEntity { /// <summary>
/// 书名 /// </summary>
public string BookName { get; set; } /// <summary>
/// 书的作者 /// </summary>
public string BookAuthor { get; set; } /// <summary>
/// 书的价格 /// </summary>
public decimal BookPrice { get; set; } /// <summary>
/// 出版商编号 /// </summary>
public int PublisherId { get; set; } /// <summary>
/// 导航属性---出版商 /// </summary>
public virtual Publisher Publisher { get; set; } } }
出版商实体：
using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace EF.Entity { public class Publisher:BaseEntity { /// <summary>
/// 出版商的名字 /// </summary>
public string PublisherName { get; set; } /// <summary>
/// 导航属性 /// </summary>
public virtual ICollection<Book> Books { get; set; } } }
然后在EF.Data项目中：
BookMap类：
using EF.Entity; using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations.Schema; using System.Data.Entity.ModelConfiguration; using System.Linq; using System.Text; using System.Threading.Tasks; namespace EF.Data { public class BookMap:EntityTypeConfiguration<Book> { public BookMap() { //配置主键
this.HasKey(s => s.ID); //配置字段
this.Property(s => s.ID).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity); this.Property(s => s.BookName).HasColumnType("nvarchar").HasMaxLength(50).IsRequired(); // this.Property(s => s.BookAuthor).HasColumnType("nvarchar(50)").IsRequired();//注意这个和BookName字段配置的区别之处:这样写EF生成不了数据库
this.Property(s => s.BookAuthor).HasColumnType("nvarchar").HasMaxLength(50).IsRequired(); this.Property(s => s.BookPrice).IsRequired(); this.Property(s => s.AddedDate).IsRequired(); this.Property(s => s.ModifiedDate).IsRequired(); this.Property(s => s.PublisherId).IsRequired(); //配置关系[一个出版商可以出版很多书籍]【外键单独配置，不是必须在Property中配置，当然也可以在Property中配置】
this.HasRequired(s => s.Publisher).WithMany(s => s.Books).HasForeignKey(s => s.PublisherId).WillCascadeOnDelete(true); //配置表名字
this.ToTable("Books"); } } }
PublisherMap类：
using EF.Entity; using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations.Schema; using System.Data.Entity.ModelConfiguration; using System.Linq; using System.Text; using System.Threading.Tasks; namespace EF.Data { public class PublisherMap:EntityTypeConfiguration<Publisher> { public PublisherMap() { //配置主键
this.HasKey(s => s.ID); this.Property(s => s.ID).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity); // this.Property(s => s.PublisherName).HasColumnType("nvarchar(50)").IsRequired();//这样写，有问题，生成不了数据库
this.Property(s => s.PublisherName).HasColumnType("nvarchar").HasMaxLength(50).IsRequired(); this.Property(s => s.AddedDate).IsRequired(); this.Property(s => s.ModifiedDate).IsRequired(); } } }
出版商我这里不做增删查改，到时候手动添加几条数据进去，然后在Book的视图中，把出版商做成下拉框的样式：所以我这里额外添加一个实体：【PublisherModel实体中的构造函数里的初始化属性嗲吗，不能忘记！！！】
using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations; using System.Linq; using System.Web; using System.Web.Mvc; namespace EF.Web.Models { public class PublisherModel { public PublisherModel() { PublisherList = new List<SelectListItem>(); } [Display(Name="PublisherName")] public int PublisherID { get; set; } public List<SelectListItem> PublisherList { get; set; } } }
数据上下文类：
using System; using System.Collections.Generic; using System.Data.Entity; using System.Data.Entity.ModelConfiguration; using System.Linq; using System.Reflection; using System.Text; using System.Threading.Tasks; namespace EF.Data { public class EFDbContext:DbContext { public EFDbContext() : 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);
} } }
Ef.Data项目和Web项目中都要加上连接字符串：
<connectionStrings>
<add name="DbConnectionString" connectionString="Server=.;Database=EFCURDDB;uid=sa;Pwd=Password_1" providerName="System.Data.SqlClient"/>
</connectionStrings>
现在看看Web项目：
using EF.Data; using EF.Entity; using EF.Web.Models; using System; using System.Collections.Generic; using System.Data.Entity; using System.Linq; using System.Web; using System.Web.Mvc; namespace EF.Web.Controllers { public class BookController : Controller { private EFDbContext db; public BookController() { db = new EFDbContext(); } #region 列表
/// <summary>
/// 列表 /// </summary>
/// <returns></returns>
public ActionResult Index() { return View(db.Set<Book>().ToList()); } #endregion
#region AddBook
/// <summary>
/// 添加Book /// </summary>
/// <returns></returns>
public ActionResult AddBook() { PublisherModel model = new PublisherModel(); List<Publisher> listPublisher = db.Set<Publisher>().ToList(); foreach (var item in listPublisher) { model.PublisherList.Add(new SelectListItem() { Text = item.PublisherName, Value = item.ID.ToString() }); } ViewBag.PublishedList = model.PublisherList; return View(); } /// <summary>
/// 添加Book /// </summary>
/// <returns></returns>
[HttpPost] public ActionResult AddBook([Bind(Include = "BookName,BookAuthor,BookPrice,AddedDate,ModifiedDate,PublisherId")] Book model) { Book addBook = new Book() { AddedDate=model.AddedDate, BookAuthor=model.BookAuthor, BookName=model.BookName, BookPrice=model.BookPrice, ModifiedDate=model.ModifiedDate, PublisherId = Convert.ToInt32( Request["PublishedName"].ToString()) //这里因为出版商我用的是另外的Model，视图中使用模型绑定只能用一个Model，所以修改和添加只能这样搞了。
}; db.Entry(addBook).State = EntityState.Added; db.SaveChanges(); return RedirectToAction("Index"); } #endregion
#region UpdateBook
/// <summary>
/// 修改Book /// </summary>
/// <param name="bookId"></param>
/// <returns></returns>
public ActionResult UpdateBook(int bookId) { PublisherModel model = new PublisherModel(); List<Publisher> listPublisher = db.Set<Publisher>().ToList(); foreach (var item in listPublisher) { model.PublisherList.Add(new SelectListItem() { Text = item.PublisherName, Value = item.ID.ToString() }); } ViewBag.PublishedList = model.PublisherList; Book bookModel = db.Set<Book>().Where(s => s.ID == bookId).FirstOrDefault(); return View(bookModel); } /// <summary>
/// 修改Book /// </summary>
/// <param name="model"></param>
/// <returns></returns>
[HttpPost] public ActionResult UpdateBook([Bind(Include = "ID,BookName,BookAuthor,BookPrice,AddedDate,ModifiedDate,PublisherId")] Book model) //注意这里一定别忘记绑定 ID列哦
{ Book bookModel = db.Set<Book>().Where(s => s.ID == model.ID).FirstOrDefault(); if (bookModel != null) { Book updatemodel = new Book() { AddedDate = model.AddedDate, BookAuthor = model.BookAuthor, ID = model.ID, ModifiedDate = model.ModifiedDate, BookName = model.BookName, BookPrice = model.BookPrice, PublisherId = Convert.ToInt32(Request["PublishedName"].ToString())//这里因为出版商我用的是另外的Model，视图中使用模型绑定只能用一个Model，所以修改和添加只能这样搞了。
}; db.Entry(bookModel).CurrentValues.SetValues(updatemodel); //保存的另外一种方式
db.SaveChanges(); return RedirectToAction("Index"); } else { return View(model); } #region 保存的方式二
//db.Entry(model).State = EntityState.Modified; //db.SaveChanges(); //return RedirectToAction("Index");
#endregion } #endregion
#region DeleteBook
public ActionResult DeleteBook(int bookId) { Book model = db.Set<Book>().Where(s => s.ID == bookId).FirstOrDefault(); return View(model); } [HttpPost] public ActionResult DeleteBook(int bookId, FormCollection form) { Book model = db.Set<Book>().Where(s => s.ID == bookId).FirstOrDefault(); db.Entry(model).State = EntityState.Deleted; db.SaveChanges(); return RedirectToAction("Index"); } #endregion } }
视图代码，我使用MVC模板生成：【适当做修改】
AddBook视图：
@model EF.Entity.Book @{ ViewBag.Title = "AddBook"; } <h2>AddBook</h2> @using (Html.BeginForm("AddBook","Book",FormMethod.Post)) { @Html.AntiForgeryToken() <div class="form-horizontal">
<h4>Book</h4>
<hr /> @Html.ValidationSummary(true, "", new { @class = "text-danger" }) <div class="form-group"> @Html.LabelFor(model => model.AddedDate, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.AddedDate, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.AddedDate, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.ModifiedDate, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.ModifiedDate, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.ModifiedDate, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.BookName, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.BookName, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.BookName, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.BookAuthor, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.BookAuthor, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.BookAuthor, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.BookPrice, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.BookPrice, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.BookPrice, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.PublisherId, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.DropDownList("PublishedName", ViewData["PublishedList"] as List<SelectListItem>) @*@Html.EditorFor(model => model.PublisherId, new { htmlAttributes = new { @class = "form-control" } })*@ @Html.ValidationMessageFor(model => model.PublisherId, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group">
<div class="col-md-offset-2 col-md-10">
<input type="submit" value="Create" class="btn btn-default" />
</div>
</div>
</div> } <div> @Html.ActionLink("Back to List", "Index") </div>
<script src="~/Scripts/jquery-1.10.2.min.js"></script>
<script src="~/Scripts/jquery.validate.min.js"></script>
<script src="~/Scripts/jquery.validate.unobtrusive.min.js"></script>
UpdateBook视图：
@model EF.Entity.Book @{ ViewBag.Title = "UpdateBook"; } <h2>UpdateBook</h2> @using (Html.BeginForm("UpdateBook","Book",FormMethod.Post)) { @Html.AntiForgeryToken() <div class="form-horizontal">
<h4>Book</h4>
<hr /> @Html.ValidationSummary(true, "", new { @class = "text-danger" }) @Html.HiddenFor(model => model.ID) <div class="form-group"> @Html.LabelFor(model => model.AddedDate, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.AddedDate, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.AddedDate, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.ModifiedDate, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.ModifiedDate, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.ModifiedDate, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.BookName, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.BookName, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.BookName, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.BookAuthor, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.BookAuthor, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.BookAuthor, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.BookPrice, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.EditorFor(model => model.BookPrice, new { htmlAttributes = new { @class = "form-control" } }) @Html.ValidationMessageFor(model => model.BookPrice, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group"> @Html.LabelFor(model => model.PublisherId, htmlAttributes: new { @class = "control-label col-md-2" }) <div class="col-md-10"> @Html.DropDownList("PublishedName", ViewData["PublishedList"] as List<SelectListItem>) @*@Html.EditorFor(model => model.PublisherId, new { htmlAttributes = new { @class = "form-control" } })*@ @Html.ValidationMessageFor(model => model.PublisherId, "", new { @class = "text-danger" }) </div>
</div>
<div class="form-group">
<div class="col-md-offset-2 col-md-10">
<input type="submit" value="Save" class="btn btn-default" />
</div>
</div>
</div> } <div> @Html.ActionLink("Back to List", "Index") </div>
<script src="~/Scripts/jquery-1.10.2.min.js"></script>
<script src="~/Scripts/jquery.validate.min.js"></script>
<script src="~/Scripts/jquery.validate.unobtrusive.min.js"></script>
注意:这里我只是把有改动的视图贴了出来，其他的视图，根据MVC模板生成之后，就不用管了。
@model IEnumerable<EF.Entity.Book> @{ ViewBag.Title = "Index"; } <h2>Index</h2>
<p> @Html.ActionLink("Create New", "AddBook") </p>
<table class="table">
<tr>
<th> @Html.DisplayNameFor(model => model.AddedDate) </th>
<th> @Html.DisplayNameFor(model => model.ModifiedDate) </th>
<th> @Html.DisplayNameFor(model => model.BookName) </th>
<th> @Html.DisplayNameFor(model => model.BookAuthor) </th>
<th> @Html.DisplayNameFor(model => model.BookPrice) </th>
<th> @Html.DisplayNameFor(model => model.PublisherId) </th>
<th></th>
</tr> @foreach (var item in Model) { <tr>
<td> @Html.DisplayFor(modelItem => item.AddedDate) </td>
<td> @Html.DisplayFor(modelItem => item.ModifiedDate) </td>
<td> @Html.DisplayFor(modelItem => item.BookName) </td>
<td> @Html.DisplayFor(modelItem => item.BookAuthor) </td>
<td> @Html.DisplayFor(modelItem => item.BookPrice) </td>
<td> @Html.DisplayFor(modelItem => item.PublisherId) </td>
<td> @Html.ActionLink("Edit", "UpdateBook", new { bookId = item.ID }) | @Html.ActionLink("Details", "DetailsBook", new { bookId = item.ID }) | @Html.ActionLink("Delete", "DeleteBook", new { bookId = item.ID }) </td>
</tr> } </table>
效果图：
总结：1.下拉框实体中，构造函数初始化语句不能忘记。
2.修改的方式，有新变化看代码；
3.模型绑定的时候，特别要注意，Bind的字段，修改的时候，Bind字段ID不能少。