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C# C# Objects Inheritance Inheritance

IMran Karim
IMran Karim
1,118 Points
Posted by IMran Karim
IMran Karim
1,118 Points

i dont understand this question

what's wrong with this code? I dont understand how to initialize the base class.

Polygon.cs 
namespace Treehouse.CodeChallenges
{
    class Polygon
    {
        public readonly int NumSides;

        public Polygon(int numSides)
        {
            NumSides = numSides;
        }

    }
    class Square : Polygon
    {
        public readonly int SideLength;

        public Square:base (int sideLength)
        {
            SideLength = sideLength;
        }
    }

    void main()
    {
        Polygon(4);
    }
}

3 Answers

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

You have the reference to base on the wrong side of the parameter.

Plus you need to pass the value 4 for the base constructor to use to initialize the number of sides:

        public Square(int sideLength) : base(4)

:point_right: You also have a stray main method definition that's not part of this challenge.

Allan Clark
Allan Clark
10,810 Points
Allan Clark
Allan Clark
10,810 Points

Syntax is a little off. The base() function allows you to specify the parameters for the constructor of the base class. Since a Square will always have 4 sides so you don't want the user of the Square class to have to explicitly code that every time. Try this: 

class Square : Polygon
    {
        public readonly int SideLength;

        public Square (int sideLength) : base(4)
        {
            SideLength = sideLength;
        }
    }