static void Main(string[] args)
{
Toy toy = new Toy();
ZincCarbonBattery zincCarbonBattery = new ZincCarbonBattery();
toy.UseBattery(zincCarbonBattery);
AlcalineBattery alcalineBattery = new AlcalineBattery();
//toy.UseBattery(alcalineBattery);
/* Want to use alcaline battery?
* We get compiler error. Toy class is tightly coupled to ZincCarbonBattery class
* We have to make some arrangement in Toy class.
* Maybe we might want to add second UseBattery overload method.
* But we have to touch Toy class. This is undesirable.
*/
}
static void Main(string[] args)
{
Toy toy = new Toy();
ZincCarbonBattery zincCarbonBattery = new ZincCarbonBattery();
toy.UseBattery(zincCarbonBattery);
AlcalineBattery alcalineBattery = new AlcalineBattery();
toy.UseBattery(alcalineBattery);
// Now we can use alcaline battery
// Toy class, is Loosely coupled to ZincCarbonBattery and AlcalineBattery classes
/* But if we want to use a kind of third battery?
* We can create a new class that implements IBattery interface.
* Then we can use new battery with toy just by calling UseBattery method.
* We dont have to make any arrangement in Toy class.
* This is what we want.
*/
}
