Area of a circle, with default integer value

Eric Kraus

static void Main(string[] args)
{
WriteLine("What is the radius of your circle: ");
WriteLine("The area of your circle is: " + circleArea(Double.Parse(ReadLine())).ToString());
ReadKey();
}
static double circleArea(double radius = 5.00)
{
return Math.PI * (radius * radius);
}

So far the code I have is working and it is able to calculate the area of a circle; however, I need to have the main method pass an integer variable (radius) with an optional default value. I thought I had it by adding =5 to my second method, but that wasn't it.

Any help would be appreciated.

3 Replies

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Laxmidhar Sahoo6y ago
hi@ Hawaldar perhaps he pass the value with space .so First stored in a string variale and then trim it

double radius = 0;
String p = Console.ReadLine();
if (Double.TryParse(p.Trim(), out radius))
Rajanikant Hawaldar6y ago
Hello Eric Kraus, Please check this code
using System;

namespace Calculator
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("What is the radius of your circle: ");

            double radius = 0;
            if (Double.TryParse(Console.ReadLine(), out radius))
            {
                Console.WriteLine("The area of your circle is: " + circleArea(radius));
            }
            else
            {
                Console.WriteLine("Invalid input");
            }

            Console.ReadKey();
        }
        static double circleArea(double radius = 5.00)
        {
            return Math.PI * (radius * radius);
        }
    }
}
Eric Kraus6y ago
To provide more context I receive an error of: System.FormatException: 'Input string was not in a correct format.' on the line below. Ideally if there isn't an input entered the default would be 4.
WriteLine("The area of your circle is: " + circleArea(Double.Parse(ReadLine())).ToString());