C＃ - IComparable對象列表之間的交集

Question

如何從兩個對象列表中找到所有實現IComparable的交集對象？

public List<T> Intersect<T>(List<T> list1, List<T> list2) where T : IComparable<T> { 
    return ... ; 
} 

Answer 1

像這樣的事情

public List<T> Intersetc<T>(List<T> list1, List<T> list2) where T : IComparable<T> 
{ 
    return list1.Intersect(list2, new MyEqualityComparer<T>()).ToList(); 
} 

public class MyEqualityComparer<T> : IEqualityComparer<T> where T : IComparable<T> 
{ 
    public bool Equals(T t1, T t2) 
    { 
     return t1.CompareTo(t2) == 0; 
    } 

    public int GetHashCode(T t) 
    { 
     return 0; 
    } 
} 

Answer 2

爲什麼不乾脆：

public List<T> Intersect<T>(List<T> list1, List<T> list2) where T : IComparable<T> 
    { 
     var intersect = list1.Intersect(list2); 
     return intersect.ToList(); 
    }