C#设计模式 – 为许多数据源设计的最佳方式

更新：

根据问题和问题陈述中提供的信息,这是一种可能的解决方案.像这样定义您的核心基础架构：

public abstract class Entity<TEntity,TDomainObject,TIRepository>
    where TEntity       : Entity<TEntity,TIRepository>
    where TDomainObject : Entity<TEntity,TIRepository>.BaseDomainObject,new()
    where TIRepository  : Entity<TEntity,TIRepository>.IBaseRepository
{

    public class BaseDomainObject {}

    public interface IBaseRepository
    {
        IEnumerable<TDomainObject> GetAll();
        IEnumerable<T> GetAllMapped<T>(Func<TDomainObject,T> mapper);
    }

    public class BaseRepository : IBaseRepository
    {
        public IEnumerable<TDomainObject> GetAll()
        {
            return new List<TDomainObject>();
        }
        public IEnumerable<T> GetAllMapped<T>(Func<TDomainObject,T> mapper)
        {
            return this.GetAll().Select(mapper);
        }
    }

}

像这样定义源实体：

public class SourceA : Entity<SourceA,SourceA.DomainObject,SourceA.IRepository>
{
    public class DomainObject : BaseDomainObject
    {
        public  string  Name;
        public  int     Age;
    }
    public interface IRepository : IBaseRepository {}
    public class Repository : BaseRepository,IRepository {}
}

public class SourceB : Entity<SourceB,SourceB.DomainObject,SourceB.IRepository>
{
    public class DomainObject : BaseDomainObject
    {
        public  string  Name;
        public  decimal Weight;
    }
    public interface IRepository : IBaseRepository {}
    public class Repository : BaseRepository,IRepository {}
}

public class SourceC : Entity<SourceC,SourceC.DomainObject,SourceC.IRepository>
{
    public class DomainObject : BaseDomainObject
    {
        public  Guid    Id;
        public  string  Name;
    }
    public interface IRepository : IBaseRepository {}
    public class Repository : BaseRepository,IRepository {}
}

然后像这样定义一个ISourceRepositoryContext接口,并在此处添加每个源存储库接口：

public interface ISourceRepositoryContext
{

    SourceA.IRepository SourceARepository { get; }
    SourceB.IRepository SourceBRepository { get; }
    SourceC.IRepository SourceCRepository { get; }

}

然后定义接口的默认实现：

public class DefaultSourceRepositoryContext : ISourceRepositoryContext
{
    public SourceA.IRepository SourceARepository => new SourceA.Repository();
    public SourceB.IRepository SourceBRepository => new SourceB.Repository();
    public SourceC.IRepository SourceCRepository => new SourceC.Repository();
}

定义结果传输对象：

public class Dog
{
    public  string  Name;
    public  int     Age;
}

public class Cat
{
    public  string  Name;
    public  decimal Weight;
}

public class Fish
{
    public  Guid    Id;
    public  string  Name;
}

public class MyObject
{
     public IEnumerable<Cat>  Cats { get; set; }
     public IEnumerable<Dog>  Dogs { get; set; }
     public IEnumerable<Fish> Fish { get; set; }
}

然后使用BusinessLogic类中的ISourceRepositoryContext：

public class BusinessLogic
{
    protected ISourceRepositoryContext repositories;

    public BusinessLogic(ISourceRepositoryContext repositories)
    {
        this.repositories = repositories;
    }

    public MyObject GetResults(string param1)
    {
        return new MyObject()
        {
            Dogs    = this.repositories.SourceARepository.GetAllMapped
            (domainObject=>new Dog
            {
                Age     = domainObject.Age,Name    = domainObject.Name
            }),Cats    = this.repositories.SourceBRepository.GetAllMapped
            (domainObject=>new Cat
            {
                Name    = domainObject.Name,Weight  = domainObject.Weight
            }),Fish    = this.repositories.SourceCRepository.GetAllMapped
            (domainObject=>new Fish
            {
                Id      = domainObject.Id,};
    }
}

我已经确认以上编译在C#6.0下.

我建议将IRepository更改为实体中的IBusiness,并将数据访问问题分解为IDataAccess接口,只有IBusiness实现者通过其构造函数接收.然后将ISourceRepositoryContext更改为ISourceEntities,并将该接口中的IRepository属性更改为IBusiness属性.

BusinessLogic类是我真正关心的部分.你确定这一课不会引起太多关注吗？这应该是UoW课吗？

有关基于类似技术的更完整解决方案,请查看我对其他问题的回答：.NET Managing Layers Relationships