C＃：如何创建一个通用的超类，以便通过非泛型子类进行扩展

问题描述

我有一堆Repository类，它们看起来都像下面这样。请注意，我省略了某些方法;

  public class SuggestionRepository：ISuggestionRepository 
 {
 private IUnitOfWork _unitOfWork ; 
 
 public SuggestionRepository（IUnitOfWork unitOfWork）
 {
 _unitOfWork = unitOfWork; 
} 
 
 public建议Load（int id）
 {
建议提示; 
 suggestion = _unitOfWork.Load< Suggestion>（id）; 
返回建议; 
} 
 
 public IQueryable< Suggestion>所有
 {
获得{return _unitOfWork.GetList< Suggestion>（）; }您可以想象我的代码库之间重复的代码数量是多少。
 
 
 
我想创建一个Repository< T>这个类是由我的仓库扩展的，所以希望我不必为每个代码编写样板代码。这个类可能如下所示： 
 
 
 内部类Repository< T>其中T：实体
 {
 private IUnitOfWork _unitOfWork; 
 
 internal Repository< T>（IUnitOfWork unitOfWork）
 {
 _unitOfWork = unitOfWork; 
} 
 
 public T Load（int id）
 {
 T t; 
 t = _unitOfWork.Load< T>（id）; 
 return t; 
} 
 
 public IQueryable< T>所有
 {
获得{return _unitOfWork.GetList< T>（）; } 
} 
} 
  
但是Visual Studio没有显示该构造函数爱一切。它会在参数列表括号内说'意外的令牌'，表示它无法在静态上下文中访问非静态字段_unitOfWork，并假装它不知道参数unitOfWork是什么。
 
 
 
显然泛型类可以有构造函数，因为它有可能创建一个List< T>例如。那么发生了什么？
解决方案
泛型类的构造函数不应该在方法名称中包含类型参数。简单地说：
 
 
 内部版本库（IUnitOfWork unitOfWork）
  
，看看你是怎么过的。
 
I have a bunch of Repository classes which all look a bit like the following. Note that I have omitted certain methods; I just want you to get a flavour.
public class SuggestionRepository : ISuggestionRepository
{
    private IUnitOfWork _unitOfWork;

    public SuggestionRepository(IUnitOfWork unitOfWork)
    {
        _unitOfWork = unitOfWork;
    }

    public Suggestion Load(int id)
    {
        Suggestion suggestion;
        suggestion = _unitOfWork.Load<Suggestion>(id);
        return suggestion;
    }

    public IQueryable<Suggestion> All
    {
        get { return _unitOfWork.GetList<Suggestion>(); }
    }
}
You'll imagine the amount of repeated code I have between my repositories.
I would like to create a Repository<T> class which is extended by my repositories so that hopefully I don't have to write boilerplate code for each one. This class might look something like the following:
internal class Repository<T> where T : Entity
{
    private IUnitOfWork _unitOfWork;

    internal Repository<T>(IUnitOfWork unitOfWork)
    {
        _unitOfWork = unitOfWork;
    }

    public T Load(int id)
    {
        T t;
        t = _unitOfWork.Load<T>(id);
        return t;
    }

    public IQueryable<T> All
    {
        get { return _unitOfWork.GetList<T>(); }
    }
}
But Visual Studio isn't showing that constructor any love at all. It's saying 'unexpected token' around the parameter list brackets, saying it can't access the non-static field _unitOfWork in a static context, and pretending it doesn't know what the parameter unitOfWork is.
Clearly generic classes can have constructors as it's possible to new up a List<T> for example. So what's going on?
 解决方案 
The constructor for a generic class should not have the type arguments in the method name. Simply say
internal Repository(IUnitOfWork unitOfWork)
and see how you get on.
                        
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