如何使用简单注入器，存储库和上下文-代码优先 [英] How to use Simple injector, Repository and Context - code first

问题描述

我正在尝试使用Simple Injector创建我的存储库并在业务逻辑层中使用它(我也想使用PerWebRequest方法).

I'm trying to use Simple Injector to create my repository and use it in the Business logic layer ( also i want to use PerWebRequest method ) .

在DAL层中，我有:

public interface IRepository<T> where T : class
{
    void Add(T entity);
    void Delete(T entity);
    void Delete(int id);
    void Update(T entity);
    T GetById(int Id);
    IQueryable<T> All();
    IEnumerable<T> Find(Func<T, bool> predicate);
}

和:

public class EFRepository<T> : IRepository<T>, IDisposable where T : class
{
    #region Members
    protected DbContext Context { get; set; }
    protected DbSet<T> DbSet { get; set; }
    #endregion

    #region Constructors

    public EFRepository(DbContext dbContext)
    {
        if (dbContext == null)
            throw new ArgumentNullException("dbContext");
        Context = dbContext;
        DbSet = Context.Set<T>();
    }

和我的环境:

public class PASContext : DbContext, IDbContext
{
    public DbSet<Product> Products { get; set; }
    public DbSet<User> Users { get; set; }

    public PASContext()
        : base("PostAndSell")
    { }
}

如您所见，EFRepository只有一个带有一个参数的构造函数-这是因为我想使用Simple Injector创建上下文的实例，并将其在创建时传递给存储库.

As you can see EFRepository has only one constructor that takes one argument - this is because i want to use Simple Injector to create an instance of the context and pass it to the repository while it is created .

在BLL中，我有一个类ProductBLL，我想从数据库中获取该类中的所有产品(使用某些GetAll方法)并将其传递，比如说HomeController.

In the BLL i have a class ProductBLL and i want to get all products in that class (with some GetAll method) from the database and pass it, lets say to HomeController .

我真的需要有人通过这个与我交谈.

I really need someone to talk me through this .

我首先从nuger安装了正确的软件包(简单注入器和简单注入器ASP.NET集成)

I started by installing the right packages from the nuger (Simple Injector and Simple Injector ASP.NET Integration)

也在我的global.asax.cs文件中的Application_Start()函数下添加了:

also in my global.asax.cs file, under Application_Start() function I`ve added :

var container = new SimpleInjector.Container();

container.RegisterPerWebRequest<IRepository<Product>, EFRepository<Product>>();

但是我在哪里创建Context实例?以及如何在业务层中访问它?

but where do i create the Context instance ? and how can i access it in the business layer ?

推荐答案

由于您可能会有许多IReposotory<T>实现(针对产品，客户，员工等)，因此最好对IRepository<T>进行一次开放的通用注册像这样:

Since you will probably have many IReposotory<T> implementations (for Product, Customer, Employee, etc), it's better make a single open generic registration for IRepository<T> like this:

container.Register(typeof(IRepository<>), typeof(EFRepository<>), Lifestyle.Scoped);

其中范围内的生活方式定义为:

Where the scoped lifestyle is defined as:

container.Options.DefaultScopedLifestyle = new WebRequestLifestyle();

此注册可确保每次请求IRepository<Product>时，Simple Injector都将返回EFRepository<Product>，对于IRepository<Customer>而言，将返回EFRepository<Customer>，依此类推，等等.

This registration ensures that Simple Injector will return a EFRepository<Product>, every time a IRepository<Product> is requested, an EFRepository<Customer> for IRepository<Customer>, and so on, and so on.

由于要在同一请求中的所有存储库上使用相同的DbContext实例，因此还应该在范围为Lifestyle的生活方式中注册DbContext:

Since you want the same DbContext instance to be used over all repositories within the same request, you should also register the DbContext with the scoped Lifestyle:

container.Register<DbContext, PASContext>(Lifestyle.Scoped);

在BLL中，我有一个ProductBLL类，我想获取所有产品 从数据库并将其传递给，比如说HomeController

In the BLL i have a class ProductBLL and i want to get all products from the database and pass it to, lets say HomeController

在那种情况下，这个ProductBLL对我来说似乎是一个无用的抽象.如果它所做的只是传递数据，则可以轻松地使HomeController直接依赖于IRepository<Product>.

In that scenario, this ProductBLL seems like a useless abstraction to me. If all it does is passing data through, you can as easily let your HomeController depend on IRepository<Product> directly.

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