Create an abstract class : Abstract Class « Class Interface « C# / C Sharp





Create an abstract class

Create an abstract class
/*
C#: The Complete Reference 
by Herbert Schildt 

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


// Create an abstract class. 
 
using System; 
 
abstract class TwoDShape {  
  double pri_width;  // private 
  double pri_height; // private 
  string pri_name;   // private 
  
  // A default constructor.  
  public TwoDShape() {  
    width = height = 0.0;  
    name = "null";  
  }  
  
  // Parameterized constructor.  
  public TwoDShape(double w, double h, string n) {  
    width = w;  
    height = h;  
    name = n;  
  }  
  
  // Construct object with equal width and height.  
  public TwoDShape(double x, string n) {  
    width = height = x;  
    name = n;  
  }  
  
  // Construct an object from an object.  
  public TwoDShape(TwoDShape ob) {  
    width = ob.width;  
    height = ob.height;  
    name = ob.name;  
  }  
  
  // Properties for width, height, and name 
  public double width { 
    get { return pri_width; } 
    set { pri_width = value; } 
  } 
 
  public double height { 
    get { return pri_height; } 
    set { pri_height = value; } 
  } 
 
  public string name { 
    get { return pri_name; } 
    set { pri_name = value; } 
  } 
  
  public void showDim() {  
    Console.WriteLine("Width and height are " +  
                       width + " and " + height);  
  }  
  
  // Now, area() is abstract. 
  public abstract double area(); 
}  
  
// A derived class of TwoDShape for triangles. 
class Triangle : TwoDShape {  
  string style; // private 
    
  // A default constructor.  
  public Triangle() {  
    style = "null";  
  }  
  
  // Constructor for Triangle.  
  public Triangle(string s, double w, double h) : 
    base(w, h, "triangle") {  
      style = s;   
  }  
  
  // Construct an isosceles triangle.  
  public Triangle(double x) : base(x, "triangle") {  
    style = "isosceles";   
  }  
  
  // Construct an object from an object.  
  public Triangle(Triangle ob) : base(ob) {  
    style = ob.style;  
  }  
  
  // Override area() for Triangle. 
  public override double area() {  
    return width * height / 2;  
  }  
  
  // Display a triangle's style. 
  public void showStyle() {  
    Console.WriteLine("Triangle is " + style);  
  }  
}  
  
// A derived class of TwoDShape for rectangles.   
class Rectangle : TwoDShape {   
  // Constructor for Rectangle.  
  public Rectangle(double w, double h) :  
    base(w, h, "rectangle"){ }  
  
  // Construct a square.  
  public Rectangle(double x) :  
    base(x, "rectangle") { }  
  
  // Construct an object from an object.  
  public Rectangle(Rectangle ob) : base(ob) { }  
  
  // Return true if the rectangle is square. 
  public bool isSquare() {   
    if(width == height) return true;   
    return false;   
  }   
     
  // Override area() for Rectangle. 
  public override double area() {   
    return width * height;   
  }   
}  
  
public class AbsShape {  
  public static void Main() {  
    TwoDShape[] shapes = new TwoDShape[4];  
  
    shapes[0] = new Triangle("right", 8.0, 12.0);  
    shapes[1] = new Rectangle(10);  
    shapes[2] = new Rectangle(10, 4);  
    shapes[3] = new Triangle(7.0);  
  
    for(int i=0; i < shapes.Length; i++) {  
      Console.WriteLine("object is " + shapes[i].name);  
      Console.WriteLine("Area is " + shapes[i].area());  
  
      Console.WriteLine();    
    }  
  }  
}


           
       










Related examples in the same category

1.Abstract Classes and Methods
2.Bank Account class is abstract since there is no single implementation for Withdrawal
3.Test abstract classTest abstract class
4.Illustrates abstract classes and methodsIllustrates abstract classes and methods
5.Demostrates the use of an abstract class, including an abstract method and abstract propertiesDemostrates the use of an abstract class, including an abstract method and abstract properties