創建泛型列表<T>並在派生類中有不同的T

Question

我有基類和管理類從它派生的使用它：

public class CBase<TC> where TC : class, new() 
    { 
     protected CBase() {} 
     protected static ConcurrentDictionary<object, Lazy<TC>> _instances = new ConcurrentDictionary<object, Lazy<TC>>(); 

     public static TC GetInstance(object key) 
     { 
      return _instances.GetOrAdd(key, k => new Lazy<TC>(() => new TC())).Value; 
     } 
    } 

public class CSeriesManager : CBase<CSeriesManager> 
    { 
     private List<CSeries.SSeries> _items = null; 
     public List<CSeries.SSeries> Series 
     { 
      get 
      { 
       if (_items == null) _items = new List<CSeries.SSeries>(); 
       return _items; 
      } 
     } 
    } 

我將有幾個管理類和他們每個人都會有類似於List的字段，並在getter中檢查NULL。是否有可能使這個領域通用，並將其移動到基類沒有多餘的拳擊/鑄造？

這是我到目前爲止有：

public class CBase<TC> where TC : class, new() 
    { 
     protected CBase() {} 
     protected List<object> _items = new List<object>(); 
     protected static ConcurrentDictionary<object, Lazy<TC>> _instances = new ConcurrentDictionary<object, Lazy<TC>>(); 

     public static TC GetInstance(object key) 
     { 
      return _instances.GetOrAdd(key, k => new Lazy<TC>(() => new TC())).Value; 
     } 

     public List<TL> GetItems<TL>() 
     { 
      return _items.ConvertAll(x => (TL)x); 
     } 
    } 

有誰知道如何改進的建議/加速呢？

Answer 1

這是你想要的東西：

public class CBase<TC, LT> where TC : class, new() 
{ 
    protected CBase() {} 
    protected static ConcurrentDictionary<object, Lazy<TC>> _instances = new ConcurrentDictionary<object, Lazy<TC>>(); 

    public static TC GetInstance(object key) 
    { 
     return _instances.GetOrAdd(key, k => new Lazy<TC>(() => new TC())).Value; 
    } 

    private List<LT> _items = null; 
    public List<LT> Series 
    { 
     get 
     { 
      if (_items == null) _items = new List<LT>(); 
      return _items; 
     } 
    } 
} 

public class CSeriesManager : CBase<CSeriesManager, SSeries> 
{ 
}