C# 这就是你的问题。选项1或3可能是您的最佳选择。ORM对象很可能是可变的，而且通常不希望覆盖Equals或GetHashCode方法。啊，好的，这更有意义。我将尝试选项1，看看它是否有效，谢谢。@user1911333您对AssociatedAttribut

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这就是你的问题。选项1或3可能是您的最佳选择。ORM对象很可能是可变的，而且通常不希望覆盖

Equals

或

GetHashCode

方法。啊，好的，这更有意义。我将尝试选项1，看看它是否有效，谢谢。@user1911333您对

AssociatedAttributes

的实现正是servy在其答案中发布的内容。如果仍要保留该实现，则可能必须实现

IEqualityComparer

而不是

IComparable

。

int numMatchingAttributes = p.AssociatedAttributes.Intersect( p.AssociatedAttributes ).Distinct( ).Count( ); 

public int CompareTo(Attribute other)
{
    return Id.CompareTo(other.Id);
}

public List<Attribute> AssociatedAttributes
        {
        get
            {
            List<Attribute> list = new List<Attribute>( );
            using (
                PredictiveRecommendor dbContext =
                    new PredictiveRecommendor()){
                if ( dbContext != null )
                    { 
                    IQueryable<Attribute> query = from a in dbContext.PageAttributes
                                                  where a.Page.Id.Equals(this.Id)
                                                  select a.Attribute;
                    list = query.ToList(); 


                    }
                }
            return list;
            }
        }

public int numberOfIntersectedAssociatedAttributes ( Page other )
        {
        using ( PredictiveRecommendor dbContext = new PredictiveRecommendor( ) )
            {
            IQueryable<Attribute> thisAssocAttributes = from a in dbContext.PageAttributes
                                                        where a.Page.Id.Equals( this.Id )
                                                        select a.Attribute;
            IQueryable<Attribute> otherAssocAttributes = from a in dbContext.PageAttributes
                                                         where a.Page.Id.Equals( other.Id )
                                                         select a.Attribute;
            IQueryable<Attribute> interSection = thisAssocAttributes.Intersect( otherAssocAttributes );

            return interSection.ToList( ).Count;
            }
        }

public class Page
{
    public List<Attribute> AssociatedAttributes
    {
        get
        {
            return new List<Attribute>() { 
                new Attribute { Value = "a" }, 
                new Attribute { Value = "b" }, 
                new Attribute { Value = "c" }, 
            };
        }
    }
}