using System; class Testing { static void Main() { double foo = 25.642; What( foo ); What( (int)foo ); } static void What( System.Object argument ) { System.Object bar = (Object)argument; Console.WriteLine( "\t{0}: {1}", argument.GetType(), argument ); Console.WriteLine("\t{0}: {1}", bar.GetType(), bar ); } } /* output: Administrator@Amnesiac>mcs test.cs Administrator@Amnesiac>./test.exe System.Double: 25.642 System.Double: 25.642 System.Int32: 25 System.Int32: 25 Administrator@Amnesiac> */