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C# C# Objects Inheritance Inheritance

Posted by Erik Hainer
Erik Hainer
3,049 Points

Cannot Initialize with base

Im not sure how to use base to initialize the NumSides to 4 in my Square Class.

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

        public Polygon(int numSides)
        {
            NumSides = numSides;
            numSides = 4;
        }
    }
    class Square : Polygon
    {
        public readonly (int SideLength)
        {
        }
        public readonly (int NumSides) : base(NumSides)
        {
        }

    }
}

1 Answer

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

There are a few issues too, here are some hints:

  • make no changes to the definition of Polygon
  • since Polygon's constructor sets NumSides, you can initialize it to 4 by calling base(4)
  • use how Polygon sets NumSides as an example of how Square needs to handle SideLength
  • Polygon can also be an example of the syntax for a constructor
Erik Hainer
Erik Hainer
3,049 Points

Thank you!!! I did all of those the first time I did the challenge except I didn't write base(4), i wrote base(numSides = 4).