A Class Can Implement More than One Interface

It’s possible for a class to implement more than one interface.

For example, a Cow class might implement both the IMoo and the IMakeMilk interfaces.  Multiple interfaces are listed after the class declaration, separated by commas.

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public class Cow : IMoo, IMakeMilk {     public void Moo() { // do mooing here }     public double Milk() { // do milking here } }

You can now use an instance of the Cow class to access members of either interface.

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Cow bossie = new Cow("Bossie", 12);   // Call both IMoo and IMakeMilk methods bossie.Moo();                        // IMoo.Moo double numGallons = bossie.Milk();   // IMakeMilk.Milk

We can also set interface variables of either interface type to refer to an instance of a Cow.

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IMoo mooStuff = bossie; IMakeMilk milkStuff = bossie;   mooStuff.Moo(); numGallons = milkStuff.Milk();

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