内部类学习

using System;
using System.Collections.Generic;

public class MyClass
{
class A
{
int a;
internal protected class B
{
public void Display()
{
A a1 = new A();
a1.a = 3;
Console.WriteLine("a={0}",a1.a);

}
}
}
public static void RunSnippet()
{
A.B b = new A.B();
b.Display();

}

#region Helper methods

public static void Main()
{
try
{
RunSnippet();
}
catch (Exception e)
{
string error = string.Format("---\nThe following error occurred while executing the snippet:\n{0}\n---", e.ToString());
Console.WriteLine(error);
}
finally
{
Console.Write("Press any key to continue...");
Console.ReadKey();
}
}

private static void WL(object text, params object[] args)
{
Console.WriteLine(text.ToString(), args);
}

private static void RL()
{
Console.ReadLine();
}

private static void Break()
{
System.Diagnostics.Debugger.Break();
}

#endregion
}