using System;
using System.Collections.Generic;
using System.Reflection;
using System.Runtime.InteropServices;
public class MainClass
{
public static void Main(){
int? x1 = null;
int? x2 = new int?();
int? y1 = 55;
int? y2 = new int?(55);
Console.WriteLine("{0}...{1}...{2}...{3}", x1, x2, y1, y2);
Console.WriteLine("x1 == null? {0}", x1 == null);
object x1o = x1;
Console.WriteLine("x1o == null? {0}", x1o == null);
Console.WriteLine("{0}...{1}", x1.GetType(), x1o.GetType());
}
}
......55...55
x1 == null? True
x1o == null? True
Unhandled Exception: System.NullReferenceException: Object reference not set to an instance of an ob
ject.
at MainClass.Main()