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嗨，这与我以前的问题有关。

EFCodeFirst : 无法定义两个对象之间的关系，因为它们附加到不同的 ObjectContext 对象

根据我上一个问题的答案中给出的参考，我不确定在使用 Ninject 和 MVC 时如何正确实现我的 DbContext 的使用。有没有人推荐如何做到这一点的例子？谢谢。

我确实在这里看到了这个 1 示例：How to handle DBContext when using Ninject 但我不确定这如何适合我项目的当前结构。

这是我的一个存储库和界面的示例，其他存储库几乎相同，目前都创建一个新上下文，我可能会更改它以将上下文注入存储库，但我认为这还不够.

public interface IRepository<T> where T : Entity {
    IQueryable<T> All { get; }
    T Find(int id);
    void InsertOrUpdate(T entity);
    void Delete(int id);
    void Save();
}

public class RecipeRepository : IRepository<Recipe>
{

    private EatRateShareDbContext context = new EatRateShareDbContext();

    public IQueryable<Recipe> All
    {
        get { return context.Recipes; }
    }

    public Recipe Find(int id)
    {
        return context.Recipes.Find(id);
    }

    public void InsertOrUpdate(Recipe recipe)
    {
        if (recipe.Id == default(int))
        {
            // New entity
            context.Recipes.Add(recipe);
        } else
        {
            // Existing entity
            context.Entry(recipe).State = EntityState.Modified;
        }
    }

    public void Delete(int id)
    {
        var recipe = context.Recipes.Find(id);
        context.Recipes.Remove(recipe);
    }

    public void Save()
    {
        try
        {
            context.SaveChanges();
        }

        catch (DbEntityValidationException databaseException)
        {
            foreach (var validationErrors in databaseException.EntityValidationErrors)
            {
                foreach (var validationError in validationErrors.ValidationErrors)
                {
                    Trace.TraceInformation("Property: {0} Error: {1}", validationError.PropertyName, validationError.ErrorMessage);
                }
            }
        }


    }
}

这是我的 DbContext

public class ERSDbContext : DbContext
{
    public DbSet<Recipe> Recipes { get; set; }
    public DbSet<Ingredient> Ingredients { get; set; }
    public DbSet<Review> Reviews { get; set; }
    public DbSet<Course> Courses { get; set; }
    public DbSet<Cuisine> Cuisines { get; set; }
    public DbSet<Member> Members { get; set; }
    public DbSet<Step> Steps { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        // have to specify these mappings using the EF Fluent API otherwise I end up with
        // the foreign key fields being placed inside the Recipe and Member tables, which wouldn't
        // give a many-to-many relationship
        modelBuilder.Entity<Recipe>()
            .HasMany(r => r.Members)
            .WithMany(m => m.Recipes)
        .Map(x => {
            x.ToTable("Cookbooks"); // using a mapping table for a many-to-many relationship
            x.MapLeftKey("RecipeId");
            x.MapRightKey("MemberId");
        });

        modelBuilder.Entity<Recipe>()
            .HasRequired(x => x.Author)
            .WithMany()
            .WillCascadeOnDelete(false);

    }
}

我使用 Ninject 将我的存储库注入到控制器中，如图所示

    public class RecipesController : Controller
    {
        private readonly IRepository<Member> memberRepository;
        private readonly IRepository<Course> courseRepository;
        private readonly IRepository<Cuisine> cuisineRepository;
        private readonly IRepository<Recipe> recipeRepository;

        public RecipesController(IRepository<Member> memberRepository, IRepository<Course> courseRepository, IRepository<Cuisine> cuisineRepository, IRepository<Recipe> recipeRepository)
        {
            this.memberRepository = memberRepository;
            this.courseRepository = courseRepository;
            this.cuisineRepository = cuisineRepository;
            this.recipeRepository = recipeRepository;
        }
...
}

对于 Ninject，我使用的是创建 NinjectWebCommon 类的 Nuget 插件，以下是我当前的绑定。

    private static void RegisterServices(IKernel kernel)
    {
        kernel.Bind<IRepository<Recipe>>().To<RecipeRepository>();
        kernel.Bind<IRepository<Member>>().To<MemberRepository>();
        kernel.Bind<IRepository<Cuisine>>().To<CuisineRepository>();
        kernel.Bind<IRepository<Course>>().To<CourseRepository>();
        kernel.Bind<IRepository<Review>>().To<ReviewRepository>();
    }
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