1 using System.Data.Entity.ModelConfiguration;
 2 using System.Data.Entity.ModelConfiguration.Configuration;
 3
 4 using ZY.Core.Entities;
 5
 6 namespace ZY.Repositories.EntityFramework
 7 {
 8     /// <summary>
 9     /// 数据实体映射配置基类
10     /// </summary>
11     /// <typeparam name="TEntity"></typeparam>
12     /// <typeparam name="TKey"></typeparam>
13     public abstract class EntityConfigurationBase<TEntity, TKey> : EntityTypeConfiguration<TEntity>, IEntityMapper
14         where TEntity : class
15     {
16         //映射实体添加到数据上下文
17         public void RegistorTo(ConfigurationRegistrar configurations)
18         {
19             configurations.Add(this);
20         }
21     }
22 }

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 using System.Data.Entity;
 7 using System.Data.Entity.ModelConfiguration.Conventions;
 8 using System.Reflection;
 9
10 namespace ZY.Repositories.EntityFramework
11 {
12     public class BaseDbContext : DbContext
13     {
14         public BaseDbContext()
15             : base("Default")
16         { }
17
18         public BaseDbContext(string connectionString)
19             :base(connectionString)
20         { }
21
22         protected override void OnModelCreating(DbModelBuilder modelBuilder)
23         {
24             //关闭级联删除
25             modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>();
26             //获取所有映射实体类
27             IEnumerable<IEntityMapper> entityMappers = GetEntityMappers().Select(type => Activator.CreateInstance(type) as IEntityMapper).ToList();
28
29             foreach (IEntityMapper mapper in entityMappers)
30             {
31                 mapper.RegistorTo(modelBuilder.Configurations);
32             }
33         }
34
35         /// <summary>
36         /// 通过反射 获取所有实体映射对象 优化的做法是保存在缓存中
37         /// </summary>
38         /// <returns></returns>
39         private Type[] GetEntityMappers()
40         {
41             Type[] mapperTypes = Assembly.GetExecutingAssembly().GetTypes()
42             .Where(type => !String.IsNullOrEmpty(type.Namespace))
43             .Where(type => type.BaseType != null && type.BaseType.IsGenericType &&
44             type.BaseType.GetInterface(typeof(IEntityMapper).Name) == typeof(IEntityMapper)).ToArray();
45             return mapperTypes;
46         }
47     }
48 }

 1 using System.Data.Entity.Migrations;
 2
 3
 4 namespace ZY.Repositories.EntityFramework.Migrations
 5 {
 6     /// <summary>
 7     /// 自动迁移设置
 8     /// </summary>
 9     public class AutoMigrationsConfiguration : DbMigrationsConfiguration<BaseDbContext>
10     {
11         public AutoMigrationsConfiguration()
12         {
13             AutomaticMigrationsEnabled = true;//自动迁移
14             AutomaticMigrationDataLossAllowed = true;//允许数据丢失
15         }
16     }
17 }