I have this code and I am trying to calculate the area and circumference of the circle. I have tried debugging and I can see that the radius was passed but the area and circumference is not, it's always 0.

using System;

class Circle{
    double radius;
    double area;
    double circumference;

    public double Radius{set{radius = value;}}
    public double Area{set{area=value;}}
    public double Circumference{set{circumference=value;}}

    

    public Circle(double radius){
        this.radius = radius;
        area=0;
        circumference=0;
    }

    void CalculateArea(){
        area=Math.PI*Math.Pow(radius,2);
    }   

    void CalculateCircumference(){
        circumference = 2*Math.PI*radius;
    }

    public void DisplayArea(){
        System.Console.WriteLine("Area is {0}",area);
    }

    public void DisplayCircumference(){
        System.Console.WriteLine("Circumference is {0}",circumference);
    }

    
}


class TestCircle{
    public static void Main(string[] args)
    {
        System.Console.WriteLine("Enter radius: ");
        double radius=Convert.ToDouble(Console.ReadLine());
        Circle theCircle = new Circle(radius);
        theCircle.DisplayArea();
        theCircle.DisplayCircumference();
    }
}

this is the output

Enter radius: 
3
Area is 0
Circumference is 0

CodePudding user response：

You have a very strange design: set only Radius (once set I can't read it), editable (both get and set) Area: one can easily assign -1.0 to it...

Let's redesign it; we have Circle class with three properties only:

class Circle{
    // Radius, the man property we can
    //   - read it (get)
    //   - assign it, but let it be just once (so set is private) 
    public double Radius {get; private set;}
    // Area, which we can just read (get, no set)  
    public double Area => Math.PI * Radius * Radius;
    // Circumference, which we can just read (get, no set)
    public double Circumference => 2 * Math.PI * Radius;

    public Circle(double radius) {
      Radius = radius;
    }

    public void DisplayArea(){
        System.Console.WriteLine($"Area is {Area}");
    }

    public void DisplayCircumference(){
        System.Console.WriteLine($"Circumference is {Circumference}");
    }
}