实体框架5图书馆消费者需要实体框架dll？ [英] Entity Framework 5 library consumers need entity framework dlls?

问题描述

我有一个项目Project.EntityFramework，其中包含一个上下文到我的数据库。在同一解决方案Project.Business中尝试从单独的项目中消耗上下文，如：

  using（var db =新EntityFramework.Entities（））
 {
 //代码
} 
  

 错误12'EntityFramework.Entities'：在使用中使用的类型语句必须隐式转换为System.IDisposable.... 
  

现在我可以F12和钻看到它正在实现IDisposable - 如果我将参考文件dll添加到Project.Business中的实体框架中，我可以将此错误消失，但是这样会打破我想要完成的目标 - 没有任何依赖在我的业务层内的EF。

我做错了什么？或者这是怎么回事？

解决方案

要扩大@Spivonious的答案，这里是我做了什么我的DbContext上的存储库模式 - 希望它主要实现：/

  public interface IFooEntity：IDisposable 
 {
 IEnumerable< Foo>得到（）; 
} 
 
 public class FooRepository：IFooEntity 
 {
 private readonly Entities _context; 
 
 public FooService（）
 {
 this._context = new Entities（）; 
} 
 
 public IEnumerable&Foo> Get（）
 {
 return _context.Foo; 
} 
 
 public void Dispose（）
 {
 _context.Dispose（）; 
} 
} 
  

原始代码来自问题：

  using（var db = new EntityFramework.Entities（））
 {
 //代码
} 
  

更改为：

  using（var db = new EntityFramework.Repository.FooRepository（））
 {
 //代码
} 
  

这允许我的代码在单独的项目中使用我的存储库而不是上下文本身，允许业务项目不必依靠实体框架引用。

I have a Project "Project.EntityFramework" which contains a context to my db. When attempting to consume the context from a separate project within the same solution "Project.Business" like:

using (var db = new EntityFramework.Entities())
{
    // Code
}

I get the compiler error on "using":

Error   12  'EntityFramework.Entities': type used in a using statement must be implicitly convertible to 'System.IDisposable'   ....

Now I can F12 and drill down to the Entities, and see it is implementing IDisposable - I can make this error go away if I put reference dlls to entity framework in "Project.Business" but this is defeating the purpose of what I wanted to accomplish - not having any dependency on EF within my Business layer.

Am I doing something wrong? Or is this just how it has to be?

解决方案

To expand on @Spivonious' answer, here is what I did to accomplish the repository pattern on my DbContext - hopefully it's mostly implemented properly :/

public interface IFooEntity : IDisposable
{
    IEnumerable<Foo> Get();
}

public class FooRepository : IFooEntity
{
    private readonly Entities _context;

    public FooService()
    {
        this._context = new Entities();
    }

    public IEnumerable<Foo> Get()
    {
        return _context.Foo;
    }

    public void Dispose()
    {
        _context.Dispose();
    }
}

original code from question:

using (var db = new EntityFramework.Entities())
{
    // Code
}

changed to:

using (var db = new EntityFramework.Repository.FooRepository())
{
    // Code
}

this allowed my code in the separate project to use my repository rather than the context itself, allowing the business project to not have to rely on entity framework references.

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