Beispiel #1
0
        // Static method that creates concrete object but declares return base type
        // Factory method pattern
        public static D2Shape ScaleD2Shape(D2Shape d2Shape, double ratio)
        {
            D2Shape scaledShape = d2Shape.Clone();

            scaledShape.Scale(ratio);
            return(scaledShape);
        }
Beispiel #2
0
        static void Main(string[] args)
        {
            PrintBreak();

            Rectangle r1 = new Rectangle(10, 5);
            //Constructor D2Shape (1) called
            //Constructor Rectangle (1) called
            //Call Rectangle constructor with two parameters: (10, 5)

            RectangularTriangle rt1 = new RectangularTriangle(10, 5);

            //Constructor D2Shape (2) called
            //Constructor RectangularTriangle (2) called

            Console.WriteLine(r1.PrintShape());     // Area of Rectangle (10,5) is = 50
            Console.WriteLine(rt1.PrintShape());    // Area of RectangularTriangle (10,5) is = 25

            Console.WriteLine("\nProtected type or member can be accessed only by code in the same class, or in a class that is derived from that class");
            //Console.WriteLine(r1._objectNumber);                        // Compilation error -> 'D2Shape._objectNumber' is inaccessible due to its protection level
            Console.WriteLine(r1.ExampleOfPublicField);
            Console.WriteLine(r1.ExampleOfInternalField);

            Console.WriteLine("\nStatic member is callable on a class");
            Console.WriteLine("Only one copy of a static member exists");
            Console.WriteLine($"Value from static field: {D2Shape.NumberOfCreatedObjects}");

            Console.WriteLine("\nStatic methods and properties cannot access non-static fields and events in their containing type");
            D2Shape scaledR1 = D2Shape.ScaleD2Shape(r1, 2);

            Console.WriteLine(scaledR1.PrintShape());

            PrintBreak();

            //2. Polymorphism
            // Creating objects but declare them as base class
            // object method is called not the base one
            D2Shape r2  = new Rectangle(10, 5);
            D2Shape rt2 = new RectangularTriangle(10, 5);

            // This works because we used override keyword. Method is called on object instance type
            Console.WriteLine(r2.PrintShape());                          // Area of Rectangle (10,5) is = 50
            Console.WriteLine(rt2.PrintShape());                         // Area of RectangularTriangle (10,5) is = 25

            PrintBreak();

            //3. Finalizers
            // Run when object is removed by GC
            Finalizers();
            // Force to call GC to show Finalizers
            GC.Collect();
            GC.WaitForPendingFinalizers();

            PrintBreak();

            //4. Students work - Circle
            // Go to Classes file and add Circle inheriting from D2Shape
            // Uncomment code below
            Circle c1 = new Circle(5);

            Console.WriteLine(c1.PrintShape());                         // Circle area (5) is =78,53981633974483
            Console.WriteLine(c1.CalculateCircuit());                   // 31,41592653589793

            D2Shape c2 = D2Shape.ScaleD2Shape(c1, 5);

            Console.WriteLine(c2.PrintShape());                         // Circle area (25) is =1963,4954084936207
            // Console.WriteLine(c2.CalculateCircuit());                   // Not accessible for c2 -> why?

            Console.WriteLine("End of Main method");
            PrintBreak();


            // Virtual hierarchy testing (from virtual.cs):

            E e = new E();
            B b = new E();

            Console.WriteLine();
            e.fun_v1();     // E_V1
            e.fun_v2();     // E_V2
            e.fun_nv();     // E_NV

            Console.WriteLine();
            b.fun_v1();     // E_V1
            b.fun_v2();     // D_V2
            b.fun_nv();     // B_NV
        }