working on project with four classes (need serious help)

create an application with four classes. three of the classes should contain data and behavior characteristics for circle, rectangle, and cylinder. the fourth class should allow the user to input a figure type from a menu of options. prompt for appropiate values based on the inputted figure type, instantiate an object of the type entered, and display characteristics about the object.
i have code for the circle but i cant figure out how to make the main class work with the other classes (circle, rectangle, and cylinder)
here is my code for the circle:
using System;

public class Sphere
{
// obtain radius from user and display volume of sphere
public void DetermineSphereVolume()
{
Console.Write( "Enter radius of sphere: " );
double radius = Convert.ToDouble( Console.ReadLine() );

Console.WriteLine( "Volume is {0:F3}", SphereVolume( radius ) );
} // end method DetermineSphereVolume

// calculate and return sphere volume
public double SphereVolume( double radius )
{
double volume = ( 4.0 / 3.0 ) * Math.PI * Math.Pow( radius, 3 );
return volume;
} // end method SphereVolume
} // end class Sphere

// Calculate the volume of a sphere.
public class SphereTest
{
// application starting point
public static void Main( string[] args )
{
Sphere mySphere = new Sphere();
mySphere.DetermineSphereVolume();
} // end Main
} // end class SphereTest

Hi, Kel following is the solution of your query. You need to implement the factory design pattern to achieve this.

 

class Program
    
{
        static void Main(string[] 
args)
        
{
            int 
shapeType = GetShapeType();

            if 
(shapeType>3)
            
{
                

                
Console.WriteLine("Invalid shape type. Please select either 1, 2 or 
3");
                
shapeType = 
GetShapeType();
            
}

            IShape 
objShape;
            
objShape = 
ShapeFactory.GetShape(shapeType);
            
objShape.DisplayShapeDetails();
            
Console.ReadKey();
        }

        private static int GetShapeType() 

        
{
            
Console.Clear();
            
int 
shapeType;
            
Console.Write("Please enter the type of 
Shape:");
            
shapeType = 
Convert.ToInt16(Console.ReadLine());
            
return shapeType;
        
}
    }

//This enum will generalize your implementation for various classes required related to other different shapes.

 public enum 
Shape 
{ 
     Circle=1, 
     Rectangle=2, 
     Cylinder=3 
}

//This interface will be used for defining the contract for various shapes

 public interface IShape 
{ 
     void DisplayShapeDetails(); 

}

//As per the requirement specified by you ShapeFactory is the fourth class which is responsible for centralized creation of the object of type of class of the shape specified by the user

 public class 
ShapeFactory 
{ 
     public static IShape GetShape(int _shapeType) 
     { 
          
IShape objShape; 
          
switch (_shapeType) 
          
{ 
               
case 
((int)Shape.Circle): 
                    
int radius; 
                    
Console.Write("Please enter the Radius of the 
circle:"); 
                    
radius = Convert.ToInt16(Console.ReadLine()); 
                    
objShape= new Circle(radius); 
                    
break; 

               
case 
((int)Shape.Rectangle): 
                    
int length, width; 
                    
Console.Write("Please enter the Length of the 
Rectangle:"); 
                    
length = Convert.ToInt16(Console.ReadLine()); 
                    
Console.Write("Please enter the Width of the 
Rectangle:"); 
                    
width = Convert.ToInt16(Console.ReadLine()); 
                    
objShape = new Rectangle(length, 
width); 
                    
break; 

               
case 
((int)Shape.Cylinder): 
                    
int height; 
                    
Console.Write("Please enter the Height of the 
Cylinder:"); 
                    
height = Convert.ToInt16(Console.ReadLine()); 
                    
Console.Write("Please enter the Radius of the 
Cylinder:"); 
                    
radius = Convert.ToInt16(Console.ReadLine()); 
                    objShape 
= new Cylinder(height, 
radius); 
                    
break; 
               
default: 
                    
objShape = null; 
                    
break;  
          } 
          
return objShape; 
     } 
}

//Circle class

 public class 
Circle : IShape 
{ 
     private Shape 
_shapeType; 
     
private 
double _radius; 
     

     public Circle() { } 
     

     
public 
Circle(double Radius) 
     { 
          _radius = 
Radius; 
          _shapeType = 
Shape.Circle; 
     } 

     
public 
void DisplayShapeDetails() 
     { 
          
Shape test = 
(Shape)_shapeType; 
          
Console.WriteLine("Area of the 
selected shape '{0}' is {1}", Enum.GetName(typeof(Shape), 
_shapeType), CalculateArea().ToString()); 
     } 

     
private 
double CalculateArea() 
     { 
          
return 
Math.PI * (_radius * _radius); 
     } 
}

//Rectangle Class

 public class 
Rectangle : IShape 
{ 
     private Shape 
_shapeType; 
     
private 
double _length; 
     
private 
double _width; 

     public Rectangle() { } 


     
public 
Rectangle(double Length, double Width) 
     { 
          _length = 
Length; 
          _width = 
Width; 
          _shapeType = 
Shape.Rectangle; 
     } 

     
public 
void DisplayShapeDetails() 
     { 
          
Shape test = 
(Shape)_shapeType; 
          
Console.WriteLine("Area of the 
selected shape '{0}' is {1}", Enum.GetName(typeof(Shape), _shapeType), 
CalculateArea().ToString()); 
     } 

     
private 
double CalculateArea() 
     { 
          
return _length * _width; 
     
} 
}

//Cylinder class

 public class 
Cylinder : IShape 
{ 
     private Shape 
_shapeType; 
     
private 
double _height; 
     private double 
_radius; 
     
     
public Cylinder() { } 

     
public 
Cylinder(double Height, double Radius) 
     { 
          _height = 
Height; 
          _radius = 
Radius; 
          _shapeType = 
Shape.Cylinder; 
     } 

     
public 
void DisplayShapeDetails() 
     { 
          
Shape test = 
(Shape)_shapeType; 
          
Console.WriteLine("Area of the selected shape '{0}' is 
{1}", 
Enum.GetName(typeof(Shape), _shapeType), 
CalculateVolume().ToString()); 
     }

private double 
CalculateVolume() 
     
{ 
          
return 
(Math.PI * _height * _radius * 
_radius); 
     } 

}

If you need to add another shape (For example Cube) then you have define a corresponding class named 'Cube' which implements the 'IShape' interface and need to add a case for the same into the ShapeFactory class.
Please let me know if you have any queries in this reply.