namespace AreaOfVariousGeometricalShape
public static void Main(string[] args)
Console.WriteLine("Area of various geometrical shape\n");
Console.WriteLine("Select option\n[1] Area of Circle\n[2] Area of Rectangle\n[3] Area of Triangle");
Console.Write("Enter your option: ");
String option = Console.ReadLine();
if (int.TryParse(option, out intInput) == true)
double doubleRadiusCircle;
double doubleLengthRectangle;
double doubleWidthRectangle;
double doubleBaseTriangle;
double doubleHeightTriangle;
Console.Write("Enter radius of the circle: ");
String radius = Console.ReadLine();
if (double.TryParse(radius, out doubleRadiusCircle) == true)
if (doubleRadiusCircle > 0)
double area = 3.1416 * (doubleRadiusCircle * doubleRadiusCircle);
Console.Write("\nThe area of the circle is {0:#,0.0000}.", area);
Console.WriteLine("Input error. Please input a positive value of radius.");
Console.WriteLine("Invalid radius.");
Console.Write("Enter length of the rectangle: ");
String lengthRectangle = Console.ReadLine();
if (double.TryParse(lengthRectangle, out doubleLengthRectangle) == true)
if (doubleLengthRectangle > 0)
Console.Write("Enter width of the rectangle: ");
String widthRectangle = Console.ReadLine();
if (double.TryParse(widthRectangle, out doubleWidthRectangle) == true)
if (doubleWidthRectangle > 0)
double area = doubleWidthRectangle * doubleLengthRectangle;
Console.Write("\nThe area of the rectangle is {0:#,0.0000}.", area);
Console.WriteLine("Input error. Please input a positive value of width.");
Console.WriteLine("Invalid width.");
Console.WriteLine("Input error. Please input a positive value of length.");
Console.WriteLine("Invalid length.");
Console.Write("Enter base of the triangle: ");
String widthTriangle = Console.ReadLine();
if (double.TryParse(widthTriangle, out doubleWidthRectangle) == true)
if (doubleWidthRectangle > 0)
Console.Write("Enter height of the triangle: ");
String heightTriangle = Console.ReadLine();
if (double.TryParse(heightTriangle, out doubleHeightTriangle) == true)
if (doubleHeightTriangle > 0)
double area = 0.5 * doubleWidthRectangle * doubleHeightTriangle;
Console.Write("\nThe area of the triangle is {0:#,0.0000}.", area);
Console.WriteLine("Input error. Please input a positive value of height.");
Console.WriteLine("Invalid height.");
Console.WriteLine("Input error. Please input a positive value of base.");
Console.WriteLine("Invalid base.");
Console.Write("Select from 1-3 only.");
Console.Write("Invalid input.");