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6.4 The Surface class

  1. Create a new class Surface according to the code below: 

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    namespace Geometry.Models
{
    public class Surface
    {
        private double _length;
        private double _width;
        public List<Shape> MyShapes;

        public Surface(double length, double width)
        {
            _length = length;
            _width = width;
            MyShapes = new List<Shape>();
        }

        public void AddShape(Shape shape)
        {
            MyShapes.Add(shape);
        }

        public override string ToString()
        {
            string result = "";
            if (MyShapes.Count > 0)
            {
                foreach (Shape shape in MyShapes)
                {
                    result += shape.ToString() + "\n\n";
                }
            }
            return result;
        }
    }
}
    • In this class, a List<Shape> is created of the abstract class Shape.
    • The AddShape() method only knows the abstract class Shape.
    • The ToString() method calls the ToString() method of the objects in the list.

    The surface is filled according to the diagram below:

    Surface layout with rectangles

  2. Add the following code to your Main method: 

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    Surface surface = new Surface(10, 7);
surface.AddShape(new Rectangle(3, 3, new Point(0, 7), "red"));
surface.AddShape(new Rectangle(3, 2, new Point(0, 4), "yellow"));
surface.AddShape(new Rectangle(5, 2, new Point(0, 2), "green"));
surface.AddShape(new Rectangle(2, 5, new Point(3, 7), "purple"));
surface.AddShape(new Rectangle(5, 4, new Point(5, 7), "orange"));
surface.AddShape(new Rectangle(5, 3, new Point(5, 3), "blue"));
Console.WriteLine(surface);

  3. Run your program. The output shows the information for each shape.

    Below you fill the following surface:

    Surface layout with rectangles and circles

  4. Add the following code and run your program: 

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    Surface surface2 = new Surface(10, 7);
surface2.AddShape(new Rectangle(3, 4, new Point(0, 7), "red"));
surface2.AddShape(new Circle(1.5, new Point(1.5, 1.5), "yellow"));
surface2.AddShape(new Rectangle(2, 7, new Point(3, 7), "green"));
surface2.AddShape(new Rectangle(1, 4, new Point(5, 7), "orange"));
surface2.AddShape(new Circle(2, new Point(8, 5), "purple"));
surface2.AddShape(new Rectangle(5, 3, new Point(5, 3), "blue"));
Console.WriteLine(surface2);

    The output shows the correct information for each shape.