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// Unbox the reference back into a corresponding short.

short anotherShort = (short)objShort;

Again, it is mandatory that you unbox into an appropriate data type. Thus, the following

unboxing logic generates an InvalidCastException exception:

// Illegal unboxing.

static void Main(string[] args)

{

short s = 25;

object objShort = s;

try

{

// The type contained in the box is NOT an int, but a short!

int i = (int)objShort;

}

catch(InvalidCastException e)

{

Console.WriteLine("OOPS!\n{0} ", e.ToString());

}

}

At first glance, boxing/unboxing may seem like a rather uneventful language feature that is

more academic than practical. In reality, the (un)boxing process is very helpful in that it allows us to

assume everything can be treated as a System.Object, while the CLR takes care of the memory-

related details on our behalf.

To see a practical use of this technique, assume you have created a System.Collections.

ArrayList to hold numeric (stack-allocated) data. If you were to examine the members of

ArrayList, you would find they are typically prototyped to receive and return System.Object types:

public class System.Collections.ArrayList : object,

System.Collections.IList,

System.Collections.ICollection,

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