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C# C# Objects Inheritance Inheritance

Kimmo Ojala
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Kimmo Ojala
Python Web Development Techdegree Student 8,257 Points

How to pass an argument to base constructor

Hi,

There must be something wrong with my code because I get an error message. I'm trying to initialize the numSides parameter of the child class Square by passing 4 to the parent class constructor. What am I doing wrong?

BR, Kimmo

Polygon.cs
namespace Treehouse.CodeChallenges
{
     class Square : Polygon
     {
            public readonly int SideLength;

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

    class Polygon
    {
        public readonly int NumSides;

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

1 Answer

Steven Parker
Steven Parker
231,198 Points

Right technique, wrong value.

When they say "by passing 4 to the parent class constructor", they mean 4 — literally ("base(4)").

Also, Square should only take one argument. And you may need to define it after Polygon.

Kimmo Ojala
seal-mask
.a{fill-rule:evenodd;}techdegree
Kimmo Ojala
Python Web Development Techdegree Student 8,257 Points

Thanks Steven. The solution was so literal I just couldn't think of it. Kind of funny, what I tried didn't look right to me, but I would have never guessed that they mean literally what they say. Thanks again!