通用存储库，CreateObjectSet< T>（）方法 [英] Generic Repository, CreateObjectSet<T>() Method

问题描述

我正在尝试实现一个通用存储库，现在我已经拥有了：

I was trying to implement a generic repository, and I have this right now:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Data;
using System.Data.Entity.Core.Objects;
using Web_API.Models;

namespace Web_API.DAL
{
    class GenericRepository<T> : IRepository<T> where T : class
    {
        private ApplicationDbContext entities = null;
        IObjectSet<T> _objectSet;

        public GenericRepository(ApplicationDbContext _entities)
        {
            entities = _entities;
            _objectSet = entities.CreateObjectSet<T>();
        }

        ...

我遇到了麻烦调用此方法：
entities.CreateObjectSet< T>（）;
应该没问题，但是我得到了这个错误：

I'm having trouble with this method call: entities.CreateObjectSet<T>(); It should be fine, however I get this error:

我已经将System.Data.Entity添加到我的项目，目前我不知道该怎么办。我正在按照本教程 http：// www .codeproject.com / Articles / 770156 /了解存储库和工作单位模式。有人知道如何解决此问题吗？

I have already added the System.Data.Entity to my project and at this point I don't know what else to do. I am following this tutorial http://www.codeproject.com/Articles/770156/Understanding-Repository-and-Unit-of-Work-Pattern. Does anyone know how to fix this issue?

推荐答案

您将需要更改方法，如下所示：

You will need to change your method to look like this:

public GenericRepository(ApplicationDbContext _entities)
{
    entities = _entities;
    _objectSet = entities.Set<T>(); //This line changed.
}

这应该具有您想要的功能。
.Set< T>（）是返回所使用类型的 DbSet 的通用方法

This should have the function that you desire. The .Set<T>() is the generic method that returns the DbSet of the type used.

更新：

随着返回类型的更改，您将需要更改 _objectSet 类型。

With the change in return type you will need to change your _objectSet type as well.

DbSet<T> _objectSet;

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