A multilevel hierarchy 1 : Class Inheritance : Class Interface C# Source Code

    

/*
C#: The Complete Reference 
by Herbert Schildt 

Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/


// A multilevel hierarchy. 
 
using System; 
 
class TwoDShape { 
  double pri_width;  // private 
  double pri_height; // private  
 
  // Default constructor. 
  public TwoDShape() { 
    width = height = 0.0; 
  } 
 
  // Constructor for TwoDShape. 
  public TwoDShape(double w, double h) { 
    width = w; 
    height = h; 
  } 
 
  // Construct object with equal width and height. 
  public TwoDShape(double x) { 
    width = height = x; 
  } 
 
  // Properties for width and height. 
  public double width { 
     get { return pri_width; } 
     set { pri_width = value; } 
  } 
 
  public double height { 
     get { return pri_height; } 
     set { pri_height = value; } 
  } 
 
  public void showDim() { 
    Console.WriteLine("Width and height are " + 
                       width + " and " + height); 
  } 
} 
 
// A derived class of TwoDShape for triangles. 
class Triangle : TwoDShape { 
  string style; // private 
   
  /* A default constructor. This invokes the default 
     constructor of TwoDShape. */ 
  public Triangle() { 
    style = "null"; 
  } 
 
  // Constructor 
  public Triangle(string s, double w, double h) : base(w, h) { 
    style = s;  
  } 
 
  // Construct an isosceles triangle. 
  public Triangle(double x) : base(x) { 
    style = "isosceles";  
  } 
 
  // Return area of triangle. 
  public double area() { 
    return width * height / 2; 
  } 
 
  // Display a triangle's style. 
  public void showStyle() { 
    Console.WriteLine("Triangle is " + style); 
  } 
} 
 
// Extend Triangle. 
class ColorTriangle : Triangle { 
  string color; 
 
  public ColorTriangle(string c, string s, 
                       double w, double h) : base(s, w, h) { 
    color = c; 
  } 
 
  // Display the color. 
  public void showColor() { 
    Console.WriteLine("Color is " + color); 
  } 
} 
 
public class Shapes6 { 
  public static void Main() { 
    ColorTriangle t1 =  
         new ColorTriangle("Blue", "right", 8.0, 12.0); 
    ColorTriangle t2 =  
         new ColorTriangle("Red", "isosceles", 2.0, 2.0); 
 
    Console.WriteLine("Info for t1: "); 
    t1.showStyle(); 
    t1.showDim(); 
    t1.showColor(); 
    Console.WriteLine("Area is " + t1.area()); 
 
    Console.WriteLine(); 
 
    Console.WriteLine("Info for t2: "); 
    t2.showStyle(); 
    t2.showDim(); 
    t2.showColor(); 
    Console.WriteLine("Area is " + t2.area()); 
  } 
}