DDD-EF-数据仓储

　　关系图

     

一、分层

二、DomainObjects构建edmx

三、EFRepositoryDemo.Domain定义仓储接口

public interface IRepository<T>
        where T : class
    {
        void Add(T entity);
        void AddAll(IEnumerable<T> entities);
        void Update(T entity);
        void Update(IEnumerable<T> entities);
        void Delete(T entity);
        void Delete(Expression<Func<T, bool>> where);
        void DeleteAll(IEnumerable<T> entities);

        void Clear();
        T GetById(long Id);
        T GetById(string Id);
        T Get(Expression<Func<T, bool>> where);
        IEnumerable<T> GetAll();
        IEnumerable<T> GetMany(Expression<Func<T, bool>> where);
        IEnumerable<T> GetAllLazy();
    }

四、Infrastructure层 仓储的抽象基类（EF的CRUD）

Repository很明显的一个特征 是 内部没有SaveChanges()

public abstract class EFRepositoryBase<T> where T : class
    {
        private Db1DbContext dataContext;
        private readonly DbSet<T> dbset;

        protected IDatabaseFactory DatabaseFactory
        {
            get;
            private set;
        }

        protected Db1DbContext DataContext
        {
            get { return dataContext ?? (dataContext = DatabaseFactory.Get()); }
        }

        protected EFRepositoryBase(IDatabaseFactory databaseFactory)
        {
            DatabaseFactory = databaseFactory;
            dbset = DataContext.Set<T>();
        }

        public virtual void Add(T entity)
        {
            dbset.Add(entity);
        }

        //新增方法
        public virtual void AddAll(IEnumerable<T> entities)
        {
            dbset.AddRange(entities);
        }

        public virtual void Update(T entity)
        {
            dbset.Attach(entity);
            dataContext.Entry(entity).State = EntityState.Modified;
        }

        //新增方法
        public virtual void Update(IEnumerable<T> entities)
        {
            foreach (T obj in entities)
            {
                dbset.Attach(obj);
                dataContext.Entry(obj).State = EntityState.Modified;
            }
        }

        public virtual void Delete(T entity)
        {
            dbset.Remove(entity);
        }

        public virtual void Delete(Expression<Func<T, bool>> where)
        {
            IEnumerable<T> objects = dbset.Where<T>(where).AsEnumerable();
            dbset.RemoveRange(objects);
        }

        //新增方法
        public virtual void DeleteAll(IEnumerable<T> entities)
        {
            dbset.RemoveRange(entities);
        }

        public virtual void Clear()
        {
            throw new NotImplementedException();
        }

        public virtual T GetById(long id)
        {
            return dbset.Find(id);
        }

        public virtual T GetById(string id)
        {
            return dbset.Find(id);
        }

        public virtual IEnumerable<T> GetAll()
        {
            return dbset.ToList();
        }

        public virtual IEnumerable<T> GetMany(Expression<Func<T, bool>> where)
        {
            return dbset.Where(where).ToList();
        }

        public T Get(Expression<Func<T, bool>> where)
        {
            return dbset.Where(where).FirstOrDefault<T>();
        }

        public virtual IEnumerable<T> GetAllLazy()
        {
            return dbset;
        }

    }

五、Repository 

    public interface IStuEducationRepo : IRepository<TB_Stu_Education>
    {

    }

    public class StuEducationRepo : RepositoryBase<TB_Stu_Education>, IStuEducationRepo
    {
        public StuEducationRepo(IDatabaseFactory databaseFactory)
            : base(databaseFactory)
        {

        }

    }

六、工作单元

在进行数据库的CUD操作时，因为Repository内部没有做SaveChanges()操作

所以要增加工作单元，进行包裹

    public interface IUnitOfWork
    {
        void Commit();
        void CommitAsync();
    }

public class UnitOfWork : IUnitOfWork
    {
        private readonly IDatabaseFactory databaseFactory;
        private Db1DbContext dataContext;

        public UnitOfWork(IDatabaseFactory databaseFactory)
        {
            this.databaseFactory = databaseFactory;
        }

        protected Db1DbContext DataContext
        {
            get { return dataContext ?? (dataContext = databaseFactory.Get()); }
        }

        public void Commit()
        {
            DataContext.SaveChanges();
        }

        public void CommitAsync()
        {
            DataContext.SaveChangesAsync();
        }

    }

七、Autofac注册

            var builder = new ContainerBuilder();
            builder.RegisterApiControllers(Assembly.GetExecutingAssembly());

            
            builder.RegisterType<DatabaseFactory>().As<IDatabaseFactory>().InstancePerLifetimeScope();
            builder.RegisterType<UnitOfWork>().As<IUnitOfWork>().InstancePerLifetimeScope();

            builder.RegisterAssemblyTypes(typeof(StuEducationRepo).Assembly)
                .Where(t => t.Name.EndsWith("Repo"))
                .AsImplementedInterfaces().InstancePerLifetimeScope();

            builder.RegisterWebApiFilterProvider(GlobalConfiguration.Configuration);
            IContainer container = builder.Build();
            var resolver = new AutofacWebApiDependencyResolver(container);

            // Configure Web API with the dependency resolver.
            GlobalConfiguration.Configuration.DependencyResolver = resolver;

八、调用示例

// GET api/<controller>/5
        public string Get(int id)
        {

            var stuAccount = _stuAccountRepo.Get(p => p.UserId == 20987);
            if (stuAccount != null)
            {
                stuAccount.UserName = "张冬林Test";
            }

            var stuEducation = _stuEducationRepo.GetMany(p => p.UserId == 20987);
            if (stuEducation != null && stuEducation.Count() > 0)
            {
                foreach (var i in stuEducation)
                {
                    i.ModifyDate = new DateTime(2016, 06, 14);
                }
            }

            _unitOfWork.Commit();

            return "value";
        }

九、总结说明

　　1、Global Autofac注册，以保证在一次Http请求的生命周期内的DbContext是单例的

        builder.RegisterType<DatabaseFactory>().As<IDatabaseFactory>().InstancePerLifetimeScope();

        private Db1DbContext dataContext;

        public Db1DbContext Get()
        {
            return dataContext ?? (dataContext = new Db1DbContext());
        }

　　这样Repository和UnitOfWork的DbContext 是一个对象，即同一个数据库上下文。所以 实现了 CRUD 与 数据持久化 两个步骤的分离

        public virtual void Update(T entity)
        {
            dbset.Attach(entity);
            dataContext.Entry(entity).State = EntityState.Modified;
        }

        private readonly IDatabaseFactory databaseFactory;
        private Db1DbContext dataContext;

        public UnitOfWork(IDatabaseFactory databaseFactory)
        {
            this.databaseFactory = databaseFactory;
        }

        protected Db1DbContext DataContext
        {
            get { return dataContext ?? (dataContext = databaseFactory.Get()); }
        }

        public void Commit()
        {
            DataContext.SaveChanges();
        }

 　2、Entity Framework本身就是一仓储，但DDD的这种设计并非画蛇添足。接口定义与代码实现的分离，可以不用关心ORM，可以不用关心是何种DB

　　附：源码下载