使用控制器实现存储库

Question

我正在自学 c#sharp 并玩弄 Entity Framework Core 和存储库模式。我已经设法让 EFcore 正常工作，从本地 sql 保存等中提取信息。我现在正试图通过存储库让它工作。 我为每种方法创建了一个 IrepositoryFile 和 Repository：

 public interface ICustomerRepository
{
    IEnumerable<Customer> GetCustomers();
    Customer GetCustomerById(int customerId);
    void InsertCustomer(Customer customer);
    void DeleteCustomer(int customerId);
}
 public class CustomerRepository : ICustomerRepository
{
    private masterContext context;

    public IEnumerable<Customer> GetCustomers()
    {
        return context.Customer.ToList();
    }

    public void InsertCustomer(Customer customer)
    {
        context.Customer.Add(customer);
        context.SaveChanges();
    }

    public void DeleteCustomer(int customerId)
    {
        //Customer c = context.Customer.Find(customerID);
        var cc = context.Customer.Where(ii => ii.CustomerId == customerId);
        context.Remove(cc);
        context.SaveChanges();
    }

    public Customer GetCustomerById(int customerId)
    {
        var result = (from c in context.Customer where c.CustomerId == customerId select c).FirstOrDefault();
        return result;
    }
}

我现在正在努力让它工作并采取下一步将其放入控制器以显示在 html 页面上。

这是我通过控制器实现存储库的尝试：

    using System.Collections.Generic;
using CustomerDatabase.Core.Interface;
using CustomerDatabase.Core.Models;
using Microsoft.AspNetCore.Mvc;

namespace CustomerDatabase.Core.Controllers
{
    public class CustomerController2 : Controller
    {
        private readonly ICustomerRepository _repository = null;
        public CustomerController2()
        {
            this._repository = new CustomerRepository();
        }
        public CustomerController2(ICustomerRepository repository)
        {
            this._repository = repository;
        }

        public ActionResult Index()
        {
            List<Customer> model = (List<Customer>)_repository.GetCustomers();
            return View(model);
        }

        public ActionResult New()
        {
            return View();
        }

        public ActionResult Insert(Customer obj)
        {
            _repository.InsertCustomer(obj);
            _repository.Save();
            return View();
        }

        public ActionResult Edit(int id)
        {
            Customer existing = _repository.GetCustomerById(id);
            return View(existing);
        }

    }
}

但我得到这个错误：

Multiple constructors accepting all given argument types have been found in type 'CustomerDatabase .Core. Controllers. CustomerController. There should only be one applicable constructor.

请有人帮忙=-说清楚，因为我不引用掌握所有技术术语

Answer 1

我认为你的问题在于这两个构造函数：

public CustomerController2()
{
    this._repository = new CustomerRepository();
}

public CustomerController2(ICustomerRepository repository)
{
    this._repository = repository;
}

从一点点阅读来看，内置解析器似乎不支持公开多个构造函数的类型。见this linked question。