比较 C# 中深度嵌套字典的 2 个对象

Question

I have a deep nested dictionaries:

var a1 = new Dictionary<string, Dictionary<string, Dictionary<string, Person>>>();
var a2 = new Dictionary<string, Dictionary<string, Dictionary<string, Person>>>();

where Person is some data structure containing members like name , family , age ...

public class Person
{
    public string name{ get; set; }
    public string family{ get; set; }
    public int age { get; set; }
}

I want to compare between a1 and a2 and especially between the Person's members. What is the best way to do that?

Answer 1

There is no out of the box solution that I can think of as deep comparison of objects is not given by libraries just because it is not a trivial task to define in a generic way that would cover most use cases. For you specific one it is fairly easy to implement. You just need to write 2 methods on that compares dictionaries and one that compares the objects:

void Compare<T, G>(Dictionary<T, G> first, Dictionary<T, G> second)
{
    foreach (var item in first)
    {
        if (!second.ContainsKey(item.Key)) Assert.Fail();

        var secondValue = second[item.Key];

        Compare(item.Value, secondValue);
    }
}

void Compare<T>(T first, T second)
{
    if (first is Dictionary<string, Dictionary<string, Dictionary<string, Person>>> f)
    {
        Compare(f, (Dictionary<string, Dictionary<string, Dictionary<string, Person>>>)(object)second);
    }
    else if (first is Dictionary<string, Dictionary<string, Person>> f1)
    {
        Compare(f1, (Dictionary<string, Dictionary<string, Person>>)(object)second);
    }
    else if (first is Dictionary<string, Person> f2)
    {
        Compare(f2, (Dictionary<string, Person>)(object)second);
    }
    else
    {
        foreach (var property in typeof(T).GetRuntimeProperties())
        {
            Assert.AreEqual(property.GetValue(first), property.GetValue(second));
        }
    }
}

there is a lot not covered by this code snippet but you can expand of it to match your use cases.