This print for content only-size & color not accurate 7" X 9-1/4" / casebound / malloy

// Call Points property defined by IPointy.

Hexagon hex = new Hexagon();

Console.WriteLine("Points: {0}", hex.Points);

Console.ReadLine();

}

This approach works fine in this particular case, given that you are well aware that the Hexagon

type has implemented the interface in question and therefore has a Points property. Other times,

however, you may not be able to determine which interfaces are supported by a given type. For

example, assume you have an array containing 50 Shape-compatible types, only some of which

support IPointy. Obviously, if you attempt to invoke the Points property on a type that has not

implemented IPointy, you receive an error. Next question: how can we dynamically determine the

set of interfaces supported by a type?

One way to determine at runtime whether a type supports a specific interface is to make

use of an explicit cast. If the type does not support the requested interface, you receive an

InvalidCastException. To handle this possibility gracefully, make use of structured exception

handling, for example:

C H A P T E R   9  

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8849CH09.qxd  10/1/07  10:41 AM  Page 276

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static void Main(string[] args)

{

...