EF6.0+APS.NET MVC5.0项目初探三（code first实体映射到数据库）

浏览数：57 / 时间：2015年06月12日

到这里架构就搭建完了，该向里面填充东西的时候了，如上篇：EF6.0+APS.NET MVC5.0项目初探二（类库引用关系及说明）

第一步 :在需要添加EF的类库Domain.DbContext上右击-》管理NuGet程序包-》找到Entity FrameWork下载安装。

如图：

第二步：新建DbContext

第三步：在类库Domain.Entity上添加引用System.ComponentModel.DataAnnotations(用于验证的引用) 并新建实体类。

 1 using System;
 2 using System.Collections.Generic;
 3 using System.ComponentModel.DataAnnotations;
 4 using System.Linq;
 5 using System.Text;
 6 using System.Threading.Tasks;
 7 
 8 namespace Domain.Entity
 9 {
10     public abstract  class BaseEntity
11     {
12         //如果类的属性名为“ID”（不区分大小写）或类名的后面跟有“ID”，则 Code First 会推断该属性是主键。如果主键属性的类型为数值或 GUID，则将其配置为标识列。
13         //int类型的自动定义为自增长   
14         //自定义增长方式
15         //[System.ComponentModel.DataAnnotations.Schema.DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.None)]
16         [Key]
17         [Display(Name = "编号")]
18         public int Id { get; set; }
19         [Display(Name = "排序")]
20         [Required(ErrorMessage = "必填项{0}！"), Range(0, int.MaxValue, ErrorMessage = "必填项{0}！")]
21         public int Sort { get; set; }
22         [Display(Name = "备注")]
23         [MaxLength(64, ErrorMessage = "{0}最大长度{1}！")]
24         public string Remark { get; set; }
25         [Display(Name = "是否删除")]
26         public bool Deleted { get; set; }
27         public int? AddUser { get; set; }
28         [DisplayFormat(ApplyFormatInEditMode = true, ConvertEmptyStringToNull = true, DataFormatString = "{0:yyyy-MM-dd HH mm}", HtmlEncode = false, NullDisplayText = "数据无效")]
29         public DateTime? AddTime { get; set; }
30         public int? ModUser { get; set; }
31         [DisplayFormat(ApplyFormatInEditMode = true, ConvertEmptyStringToNull = true, DataFormatString = "{0:yyyy-MM-dd  HH mm}", HtmlEncode = false, NullDisplayText = "数据无效")]
32         public DateTime? ModTime { get; set; }
33 
34         //详见：http://msdn.microsoft.com/zh-cn/data/jj591583.aspx
35         //主键：KEY  [Key]
36         //自增长 ：[System.ComponentModel.DataAnnotations.Schema.DatabaseGenerated (System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.None)]
37         //忽略列 忽略表 映射 ：[NotMapped]
38         //定义外键方式：[ForeignKey("DestinationId")]
39         //定义数据类型 [Column(TypeName = "ntext")]
40         //表名及所有者 [Table("Product", Schema = "dbo")]
41     }
42 }

实体基类

 1 using System;
 2 using System.Collections.Generic;
 3 using System.ComponentModel.DataAnnotations;
 4 using System.Linq;
 5 using System.Text;
 6 using System.Threading.Tasks;
 7 
 8 namespace Domain.Entity
 9 {
10     public class T_Public_AdPosition:BaseEntity
11     {
12         [Display(Name = "广告位名称")]
13         [Required(ErrorMessage="{0}是必填项")]
14         [MaxLength(64, ErrorMessage = "{0}最大长度{1}")]       
15         public string Name { get; set; }
16         [Display(Name = "广告位宽度")]
17         [Required(ErrorMessage = "{0}是必填项")]
18         public int Width { get; set; }
19 
20         [Display(Name = "广告位长度")]
21         [Required(ErrorMessage = "{0}是必填项")]
22         public int Height { get; set; }
23 
24         [Display(Name = "广告位模板")]
25         [Required(ErrorMessage = "{0}是必填项")]
26         [MaxLength(128, ErrorMessage = "{0}最大长度{1}")]
27         public string Template { get; set; }
28     }
29 }

实体类

第四步：修改类库Domain.DbContext中的App.config文件和UI.Manage中的webconfig文件，添加连接。其中的数据库名称就是将要生成的数据库名称

  <connectionStrings>
  <add name="LimitDB" connectionString="Data Source=.;Initial Catalog=LimitDB;User ID=sa;Password=123456;MultipleActiveResultSets=True;Application Name=EntityFramework" providerName="System.Data.SqlClient" />
  </connectionStrings>

name="LimitDB"是数据库连接名称，

Initial Catalog=LimitDB是将要生成的数据库名称

App.config文件如下，webconfig文件类似修改连接

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <configuration>
 3   <configSections>
 4     <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
 5     <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
 6   </configSections>
 7   <connectionStrings>
 8     <add name="LimitDB" connectionString="Data Source=.;Initial Catalog=LimitDB;User ID=sa;Password=123456;MultipleActiveResultSets=True;Application Name=EntityFramework" providerName="System.Data.SqlClient" />
 9   </connectionStrings>
10   <entityFramework>
11     <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
12       <parameters>
13         <parameter value="v11.0" />
14       </parameters>
15     </defaultConnectionFactory>
16     <providers>
17       <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
18     </providers>
19   </entityFramework>
20 </configuration>

第五步：执行数据库迁移命令

如图：

生成如下文件：

修改生成的文件：

 1 namespace Domain.DbContext.Migrations
 2 {
 3     using System;
 4     using System.Data.Entity;
 5     using System.Data.Entity.Migrations;
 6     using System.Linq;
 7 
 8     internal sealed class Configuration : DbMigrationsConfiguration<Domain.DbContext.DbContext>
 9     {
10         public Configuration()
11         {
12             //允许自动迁移
13             //不然会报错Unable to update database to match the current model because there are pending changes and automatic migration is disabled. Either write the pending model changes to a code-based migration or enable automatic migration. Set DbMigrationsConfiguration.AutomaticMigrationsEnabled to true to enable automatic migration.You can use the Add-Migration command to write the pending model changes to a code-based migration.
14 
15             //允许自动迁移
16             AutomaticMigrationsEnabled = true;
17             //自动迁移默认情况下不扔掉列在我们的数据库中的表。如果我们不希望这样的行为，我们可以告诉迁移明确允许数据丢失的配置类的AutomaticMigrationDataLossAllowed属性设置为true。
18             AutomaticMigrationDataLossAllowed = true;
19         }
20 
21         protected override void Seed(Domain.DbContext.DbContext context)
22         {
23             //  This method will be called after migrating to the latest version.
24 
25             //  You can use the DbSet<T>.AddOrUpdate() helper extension method 
26             //  to avoid creating duplicate seed data. E.g.
27             //
28             //    context.People.AddOrUpdate(
29             //      p => p.FullName,
30             //      new Person { FullName = "Andrew Peters" },
31             //      new Person { FullName = "Brice Lambson" },
32             //      new Person { FullName = "Rowan Miller" }
33             //    );
34             //
35         }
36     }
37 }