.NET Framework Standard Library Annotated Reference, Volume 1: Base Class Library and Extended Numerics Library

Example

using System;

namespace Samples
{
  public class NullReferenceExceptionSample
  {
    public static void Main()
    {
      string s = null;
      try
      {
        Console.WriteLine(s.ToUpper());
      }
      catch(NullReferenceException e)
      {
        Console.WriteLine("Exception: {0}", e);
      }
    }
  }
}

The output is

Exception: System.NullReferenceException: Object reference not set to an instance 
of an object.
   at Samples.NullReferenceExceptionSample.Main() in C:\Books\BCL\Samples\System\
NullReferenceException\NullReferenceException.cs:line 12