public static void DemoExplicitInterface()
{
Rectangle <int> rectangle = new Rectangle <int>("Rectangle With Explicit Inteface Implementation", 10, 30);
IDraw3D draw = rectangle as IDraw3D;
if (draw != null)
{
draw.Draw();
}
IDrawHologram drawHolo = rectangle as IDrawHologram;
if (drawHolo != null)
{
drawHolo.Draw();
}
}
// I'll Draw anything!
public static void DrawThisShapeIn3D(IDraw3D itf3d)
{
itf3d.Draw();
}
public static int Main(string[] args)
{
Line l = new Line();
l.Draw();
IDraw3D itfDraw3d = (IDraw3D)l;
itfDraw3d.Draw();
// First way to obtain an interface:
Circle c = new Circle("Mitch");
IPointy itfPt;
try
{
itfPt = (IPointy)c;
Console.WriteLine("Got interface using casting...");
}
catch (InvalidCastException e)
{ Console.WriteLine("OOPS! Not pointy..."); }
// Second way to obtain an interface:
Hexagon hex = new Hexagon("Fran");
IPointy itfPt2;
itfPt2 = hex as IPointy;
if (itfPt2 != null)
{
Console.WriteLine("Got interface using as keyword");
}
else
{
Console.WriteLine("OOPS! Not pointy...");
}
// Third way to grab an interface.
Triangle t = new Triangle();
if (t is IPointy)
{
Console.WriteLine("Got interface using is keyword");
}
else
{
Console.WriteLine("OOPS! Not pointy...");
}
Console.WriteLine();
// The C# base class pointer trick.
Shape[] s = { new Hexagon(), new Circle(), new Triangle("Joe"), new Circle("JoJo") };
for (int i = 0; i < s.Length; i++)
{
s[i].Draw();
// Who's pointy?
if (s[i] is IPointy)
{
Console.WriteLine("Points: {0}\n", ((IPointy)s[i]).GetNumberOfPoints());
}
else
{
Console.WriteLine(s[i].PetName + "\'s not pointy!\n");
}
// Can I draw you in 3D?
if (s[i] is IDraw3D)
{
DrawThisShapeIn3D((IDraw3D)s[i]);
}
Console.WriteLine();
}
return(0);
}
// I'll draw anyone supporting IDraw3D!
public static void DrawIn3D(IDraw3D itf3d)
{
Console.WriteLine("-> Drawing IDraw3D compatible type");
itf3d.Draw();
}
static void Main(string[] args)
{
Shape[] s = { new Hexagon(), new Circle(), new Triangle("Trident"),
new Circle("Ring") };
Console.WriteLine("\n===========================================================");
Console.WriteLine("===========================================================");
Hexagon testHexagon = new Hexagon(); // my changes create new obj for test with explicied implimentes Interface..
IDraw3D Qdraw3D = testHexagon;
Qdraw3D.Draw();
DrawIn3D(testHexagon);
testHexagon.Draw();
IDraw3D draw3D = testHexagon;
draw3D.Draw();
Console.WriteLine("===========================================================");
Console.WriteLine("===========================================================");
for (int i = 0; i < s.Length; i++)
{
// Recall the Shape base class defines an abstract Draw() member,
// so all shapes know how to draw themselves.
s[i].Draw();
// Who's pointy?
if (s[i] is IPointy)
{
Console.WriteLine("-> Points: {0} ", ((IPointy)s[i]).Points);
}
else
{
Console.WriteLine("-> {0}\'s not pointy!", s[i].PetName);
}
// Can I draw you in 3D?
if (s[i] is IDraw3D)
{
DrawIn3D((IDraw3D)s[i]);
}
Console.WriteLine("----------------------------");
}
#region Interfaces as return values
// Attempt to get IPointy.
Circle c = new Circle();
// IPointy itfPt = c as IPointy;
IPointy itfPt = ExtractPointyness(c);
if (itfPt != null)
{
Console.WriteLine("Object has {0} points.", itfPt.Points);
}
#endregion
#region Print all the members in IPointy array
Console.WriteLine("\n***** Printing out members in IPointy array *****");
IPointy[] myPointyObjects = new IPointy[] { new Hexagon(), new Spear(),
new Triangle(), new Fork(), new PitchFork() };
for (int i = 0; i < myPointyObjects.Length; i++)
{
Console.WriteLine("Object has {0} points.", myPointyObjects[i].Points);
}
#endregion
Console.ReadLine();
}