Inherit the Private Class and Access the Private Variables in C#

It's possible for a class B to inherit from a private class A if both A and B are nested within some other class C.

It's also possible to instantiate and access the private members of a private class using reflection.

Here's an example which illustrates both concepts:

using System;

using System.Reflection;

class Outer

{

private class Inner

{

internal int i = 3;

}

private class Inner2 : Inner

{

private int j = 4;

}

class Test

{

static void Main()

{

Type t = typeof(Outer);

BindingFlags bf = BindingFlags.NonPublic;

Type t2 = t.GetNestedType("Inner2", bf);

object obj = Activator.CreateInstance(t2);

BindingFlags bf2 = BindingFlags.Instance | BindingFlags.NonPublic;

FieldInfo fi = t2.GetField("i", bf2);

Console.WriteLine("i = {0}", fi.GetValue(obj)); // i = 3

FieldInfo fi2 = t2.GetField("j", bf2);

Console.WriteLine("j = {0}", fi2.GetValue(obj)); // j = 4

Console.ReadKey();

}

1 Reply

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Vulpes14y ago
Accepted answer
It's possible for a class B to inherit from a private class A if both A and B are nested within some other class C.

It's also possible to instantiate and access the private members of a private class using reflection.

Here's an example which illustrates both concepts:

using System;
using System.Reflection;

class Outer
{
private class Inner
{
internal int i = 3;
}

private class Inner2 : Inner
{
private int j = 4;
}
}

class Test
{
static void Main()
{
Type t = typeof(Outer);
BindingFlags bf = BindingFlags.NonPublic;
Type t2 = t.GetNestedType("Inner2", bf);
object obj = Activator.CreateInstance(t2);
BindingFlags bf2 = BindingFlags.Instance | BindingFlags.NonPublic;
FieldInfo fi = t2.GetField("i", bf2);
Console.WriteLine("i = {0}", fi.GetValue(obj)); // i = 3
FieldInfo fi2 = t2.GetField("j", bf2);
Console.WriteLine("j = {0}", fi2.GetValue(obj)); // j = 4
Console.ReadKey();
}
}