最近因为项目需要，研究了下EF的读写分离，所以做了一个demo进行测试，下面是项目的结构

表现层view

  主要提供Web、WebApi等表现层的解决方案

公共层public

   主要提供项目公共类库，数据缓存基础方法等

实体层model

   主要提供数据库映射模型，还有就是DDD领域操作模型

数据层Db

   主要封装EF操作基础类

数据服务层Service

   主要提供数据库操作服务、缓存操作服务

数据接口服务层inface

   主要提供数据库操作服务接口、缓存操作服务接口

1.首先是多数据库的支持，目前就支持mysql/sqlservice，如果需要添加更多的数据库支持，只需要再数据库操作类型上面添加即可

/// 
    /// 数据库类型    /// 
    public enum DbContextType : byte    {        SqlService = 1,        MySql = 2    }

分别对mysql/sqlservice的上下文操作进行封装

/// 
    /// MySql操作类    /// 
    [DbConfigurationType(typeof(MySqlEFConfiguration))]    public class MySqlContext : DbContext    {        public DbSet
      
        TestEntities { get; set; }        /// 
       
        /// 配置默认的字符串链接        /// 
        public MySqlContext() : base("DefaultConnection") {        }        /// 
       
        /// 自定义数据库链接        /// 
        /// 
               public MySqlContext(string connenction) : base(connenction) { }        /// 
       
        /// 实体对应规则的映射配置        /// 
        /// 
               protected override void OnModelCreating(DbModelBuilder modelBuilder)        {        }    }
      

/// 
    /// Sql数据库操作类    /// 
    public class SqlServiceContext : DbContext    {        /// 
        /// 配置默认的字符串链接        /// 
        public SqlServiceContext() {        }        /// 
        /// 自定义数据库链接        /// 
        ///         public SqlServiceContext(string connenction) : base(connenction) {        }        /// 
        /// 实体对应规则的映射配置        /// 
        ///         protected override void OnModelCreating(DbModelBuilder modelBuilder)        {        }    }

在view调用时候，进行ef上下文初始化只需要设置类型

/// 
    /// 数据库策略初始化类    /// 
    public static class DBInitializer    {        public static DbContextType DbContextType { get; set; }        /// 
        /// 数据库初始化策略配置        /// 
`        public static void Initialize(DbContextType ContextType)        {            string IsUsedWR = System.Configuration.ConfigurationManager.AppSettings["IsUsedWR"];            DbContextType = ContextType;            ///获得数据库最后一个版本            //   Database.SetInitializer
      
       (new MigrateDatabaseToLatestVersion
       
        ());            if (ContextType == DbContextType.SqlService)            {                Database.SetInitializer(new MigrateDatabaseToLatestVersion
        
         ());                if (IsUsedWR == "1") {                    Database.SetInitializer(new MigrateDatabaseToLatestVersion
         
          ());                }                else                {                    Database.SetInitializer
          
           (null);                }            }            else            {                Database.SetInitializer(new MigrateDatabaseToLatestVersion
           
            ()); if (IsUsedWR == "1") { Database.SetInitializer(new MigrateDatabaseToLatestVersion
            
             ()); } else { Database.SetInitializer
             
              (null); } //Database.SetInitializer
              
               (null); // Database.SetInitializer
               
                (null); } // Database.SetInitializer
                
                 (null); ///删除原来数据库 重新创建数据库 //Database.SetInitializer(new DropCreateDatabaseIfModelChanges
                 
                  ()); // Database.SetInitializer
                  
                   (new DropCreateDatabaseIfModelChanges
                   
                    ()); } }
                   
                  
                 
                
               
              
             
            
           
          
         
        
       
      

public class MvcApplication : System.Web.HttpApplication    {        protected void Application_Start()        {            AreaRegistration.RegisterAllAreas();            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);            RouteConfig.RegisterRoutes(RouteTable.Routes);            BundleConfig.RegisterBundles(BundleTable.Bundles);            //Autofac            //ContainerBuilder builder = new ContainerBuilder();            //builder.RegisterAssemblyTypes(Assembly.GetExecutingAssembly());            //IContainer container = builder.Build();            //DependencyResolver.SetResolver(new AutofacDependencyResolver(container));            //Autofac初始化过程            ContainerBuilder builder = new ContainerBuilder();            builder.RegisterControllers(System.Reflection.Assembly.GetExecutingAssembly());//注册mvc容器的实现              var assemblys = BuildManager.GetReferencedAssemblies().Cast
      
       ().ToList();            builder.RegisterAssemblyTypes(assemblys.ToArray()).Where(t => t.Name.Contains("Service")).AsImplementedInterfaces();            var container = builder.Build();            DependencyResolver.SetResolver(new AutofacDependencyResolver(container));            //初始化数据库            DBInitializer.Initialize(DbContextType.MySql);        }    }
      

通过上面多数据库的支持已经完成，下面进行读写分离，分别进行继承上述上下文操作

/// 
    /// 读    /// 
    public class WriteSqlServiceContext : SqlServiceContext    {        public WriteSqlServiceContext() : base("") { }    }    /// 
    /// 写    /// 
    public class ReadSqlServiceContext : SqlServiceContext    {        public ReadSqlServiceContext() : base("") { }    }

通过工厂类进行初始化

/// 
    /// 上下文工厂类    /// 
    public static class Contextfactory    {        /// 
        /// 获取上下文        /// 
        /// 
              public  static DbContext GetContext(DbOpertionType OpertionType)        {            DbContextType ContextType = DBInitializer.DbContextType;            if (ContextType == DbContextType.MySql)            {                if (OpertionType == DbOpertionType.Read)                    return new ReadMySqlContext();                else                    return new WriteMySqlContext();            }            else            {                if (OpertionType == DbOpertionType.Read)                    return new ReadSqlServiceContext();                else                    return new WriteSqlServiceContext();            }        }        /// 
        /// 获取上下文操作        /// 
        /// 
              ///         /// 
              public static TEntity CallContext
      
       (DbOpertionType OpertionType) where TEntity: DbContext        {            var DbContext = GetContext(OpertionType);            return (TEntity)DbContext;        }    }
      

最后配置webcofig即可

最后进行测试

public class TestController : Controller    {        private ITestService _TestServiceDb { get; set; }        public TestController(ITestService TestServiceDb) {            _TestServiceDb = TestServiceDb;        }        // GET: Test        public ActionResult Index()        {            var result = _TestServiceDb.AddEntity(new Test() { ID=Guid.NewGuid(), Age=11, CreateTime=DateTime.Now, Name="Test" });            var NewResult = _TestServiceDb.GetEntityByID(result.ID);            return View();        }    }

搞定，可能在代码上有点累赘，但是总算是可行的。

如果有兴趣的朋友可以留下邮箱，然后发全代码一起研究，谢谢！