EntityFramework用法探索（四）Repository和UnitOfWork-白红宇

EntityFramework用法探索（四）Repository和UnitOfWork

阅读量：5998 次

发布时间：2019-06-20

本文共 3603 字，大约阅读时间需要 12 分钟。

以上一篇生成代码为基础，继续探索使用方式。

引入，定义最简单的IRepository接口，仅包含增删改查接口，

1   public interface IRepository
     
      2     where T : class3   {4     IQueryable
      
        Query();5     void Insert(T entity);6     void Update(T entity);7     void Delete(T entity);8   }

引入，因为EntityFramework会负责失败回滚，所以此处只定义提交方法。

1   public interface IUnitOfWork2   {3     void Commit();4   }

实现IRepository接口，

1   public class Repository
     
       : IRepository
      
        where T : class 2   { 3     private readonly IObjectSetFactory _objectSetFactory; 4     private readonly IObjectSet
       
         _objectSet; 5  6     public Repository(IObjectSetFactory objectSetFactory) 7     { 8       _objectSetFactory = objectSetFactory; 9       _objectSet = objectSetFactory.CreateObjectSet
        
         ();10     }11 12     #region IRepository
         
           Members13 14     public IQueryable
          
            Query()15 {16 return _objectSet;17 }18 19 public void Insert(T entity)20 {21 _objectSet.AddObject(entity);22 }23 24 public void Update(T entity)25 {26 _objectSet.Attach(entity);27 _objectSetFactory.ChangeObjectState(entity, EntityState.Modified);28 }29 30 public void Delete(T entity)31 {32 _objectSet.DeleteObject(entity);33 }34 35 #endregion36 }

实现IUnitOfWork接口，

1   public class UnitOfWork : IUnitOfWork, IDisposable 2   { 3     private readonly IObjectContext _objectContext; 4  5     public UnitOfWork(IObjectContext objectContext) 6     { 7       _objectContext = objectContext; 8     } 9 10     #region IUnitOfWork Members11 12     public void Commit()13     {14       _objectContext.SaveChanges();15     }16 17     #endregion18 19     #region IDisposable Members20 21     public void Dispose()22     {23       if (_objectContext != null)24       {25         _objectContext.Dispose();26       }27 28       GC.SuppressFinalize(this);29     }30 31     #endregion32   }

CustomerRepository类的实现需要做一些配置，

1     public CustomerRepository() 2     { 3       Mapper.CreateMap
     
      (); 4       Mapper.CreateMap
      
       (); 5  6       DbContext context = new RETAILContext(); 7       DbContextAdapter contextAdaptor = new DbContextAdapter(context); 8  9       IObjectSetFactory objectSetFactory = contextAdaptor;10       _repository = new Repository
       
        (objectSetFactory);11 12       IObjectContext objectContext = contextAdaptor;13       _uow = new UnitOfWork(objectContext);14     }

则具体增删改查的逻辑实现，

1     public void InsertCustomer(DomainModels.Customer customer) 2     { 3       Customer entity = Mapper.Map
     
      (customer); 4  5       _repository.Insert(entity); 6       _uow.Commit(); 7  8       customer.Id = entity.Id; 9     }10 11     public void UpdateCustomer(DomainModels.Customer customer)12     {13       Customer entity = _repository.Query().Single(c => c.Id == customer.Id);14 15       entity.Name = customer.Name;16       entity.Address = customer.Address;17       entity.Phone = customer.Phone;18 19       _repository.Update(entity);20 21       _uow.Commit();22     }

在同样的示例下仍然可以工作，

1       ICustomerRepository customerRepository = new CustomerRepository(); 2  3       // =============== 增 =============== 4       Console.ForegroundColor = ConsoleColor.DarkRed; 5  6       DomainModels.Customer customer1 = new DomainModels.Customer() 7       { 8         Name = "Dennis Gao", 9         Address = "Beijing",10         Phone = "18888888888",11       };12       customerRepository.InsertCustomer(customer1);13       Console.WriteLine(customer1);