void ExPolyList()
{
Pen pen = new Pen();
WhiteBoardPen whiteBoardPen = new WhiteBoardPen();
List <Pen> penBox = new List <Pen>();
penBox.Add(pen);
penBox.Add(whiteBoardPen);
foreach (var item in penBox)
{
Console.ResetColor();
if (item is WhiteBoardPen)
{
(item as WhiteBoardPen).WriteToScreen("whitebord pen text");
(item as WhiteBoardPen).ImAWhiteBordPen();
}
else
{
item.WriteToScreen("normal pen text");
}
}
}
void Expoly()
{
Pen pen = new Pen();
pen.SetColor("red");
WhiteBoardPen whiteBoardPen = new WhiteBoardPen();
whiteBoardPen.SetColor("red");
whiteBoardPen.ImAWhiteBordPen();
Pen wbPen = whiteBoardPen;
//will not work - wbPen.ImAWhiteBordPen
wbPen.WriteToScreen("Poly? yes but can only call on Pen members");
}
//----- exampel code methods ------------------------------
void ExInheritance()
{
Pen pen = new Pen();
pen.WriteToScreen("Hello World!");
pen.SetColor("red");
pen.WriteToScreen("Hello World!");
WhiteBoardPen whiteBoardPen = new WhiteBoardPen();
whiteBoardPen.WriteToScreen("Im a whitebord pen");
whiteBoardPen.SetColor("red");
whiteBoardPen.WriteToScreen("Im a red whitebord pen");
}