Reflection to Get `Parent` Object [duplicate]

Answer 1

The code is messy, but it works :

public class A { public B BInstance { get; set; } }

public class Z { public B BInstance { get; set; } }

public class C { public Z BInstance { get; set; } }

public class B
{
    public List<Type> GetParentTypes()
    {
        Type thisType = this.GetType();
        FieldInfo f = null;
        PropertyInfo p = null;
        Assembly assembly = Assembly.GetAssembly(thisType);

        List<Type> types = 
            assembly.DefinedTypes
            .Where(t => t.IsClass
                && t.GetMembers().Any(m =>
            {
                if ((f = m as FieldInfo) != null)
                    return f.FieldType == thisType;
                return (p = m as PropertyInfo) != null &&
                                 p.PropertyType == thisType;
            }))
            .Select(t => t.AsType())
            .ToList();

        return types;
    }
}

class Program
{
    static void Main(string[] args)
    {
        B instance = new B();
        List<Type> types = instance.GetParentTypes();

        foreach (var type in types)
        {
            Console.WriteLine(type.Name);
        }
    }
}

Output :

A Z

Answer 2

The answer is no, as far i know, because when you write that

var t = new B () ;

the new B instance has no information on where will be stored, so as that istance has no cognition on the fact that is stored in a var, the ones in your example do not know is put in a property of an A instance.

Answer 3

Please don't actually do this...

using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Reflection;
using System.Threading;

public class Program
{
    public static void Main()
    {
        var xx = B.GetParentType();
    }
}

public class A
{
    public B b { get; set; }
}

public class B
{
    public static List<Type> GetParentType()
    {
        var q = from t in Assembly.GetExecutingAssembly().GetTypes()
                where t.IsClass && t.GetProperties().Any(p => p.PropertyType == typeof(B))
                select t;
        return q.ToList();
    }
}