比较两个复杂对象的相等性

Question

I have two List, this complex object has 4 public properties of reference type. How can i compare one list to another to find if those lists are equal in size and by values.

I have implemented Equals in ComplexObject in order to help with equality checks

public Type1 Type1 { get; set; }
public IEnumerable<Type2> Type2s{ get; set; }
public Type3 Type3{ get; set; }
public Type4 Type4 { get; set; }

public bool Equals(ComplexObject complexObject)
{
    int type2sCount = Type2s.Count();
    return Type1 .Equals(complexObject.Type1) &&
        Type3.Equals(complexObject.Type3) &&
        Type4.Equals(complexObject.Type4) &&
        Type2s.Intersect(complexObject.Type2s).Count() == type2sCount;
}

I need also to print out items that do no fit or have no pair in second list

Thanks

Answer 1

If you sort both lists first, you can use the SequencyEqual extension method to check that both sequences are equal. This method is part of System.Linq.

Here's an example:

    List<ComplexObject> list1 = new List<ComplexObject>();
    List<ComplexObject> list2 = new List<ComplexObject>();

    IOrderedEnumerable<ComplexObject> list1Sorted = list1.OrderBy(item => item.SomeProperty);
    IOrderedEnumerable<ComplexObject> list2Sorted = list2.OrderBy(item => item.SomeProperty);

    bool areEqual = list1Sorted.SequenceEqual(list2Sorted);

Answer 2

The simplest approach for the lists would be SequenceEqual , but you need to be careful about null s:

public bool Equals(ComplexObject complexObject)
{
    bool eq = Equals(Type1, complexObject.Type1)
        && Equals(Type3, complexObject.Type3)
        && Equals(Type4, complexObject.Type4);
    if (eq)
    {
        if(Type2s == null)
        {
            if(complexObject.Type2s != null) eq = false;
        } else {
            eq = complexObject.Type2s == null ? false
               : Type2s.SequenceEqual(complexObject.Type2s);
        }
    }
    return eq;
}

Answer 3

Check out the IEqualityComparer(T). You implement the interface members and if you are using LINQ, it will work, you should be able to AND the lists. http://msdn.microsoft.com/en-us/library/ms132151.aspx

Answer 4

您可以使用SequenceEqual(List1, List2)

  bool equal = Type2s.SequenceEqual(complexObject.Type2s);