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C# C# Objects Inheritance Inheritance

Cole Vanlandingham
Cole Vanlandingham
1,059 Points
Posted by Cole Vanlandingham
Cole Vanlandingham
1,059 Points

Initializing numSides

How am I supposed to initialize the numSides variable?

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(int sideLength) : base(numSides)
        {
            SideLength = sideLenght;
            numSides = 4;

        }
    }
}

3 Answers

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Anything you pass to the base constructor is used to initialize NumSides (capital "N").

So in the definition of your own constructor, you would call "base(4)" to initialize it to 4.

Also it looks like you have a typo where you have "sideLenght" instead of "sideLength".

Steve Perry
Steve Perry
8,739 Points
Steve Perry
Steve Perry
8,739 Points

So why in the video did he type base(x,y) if it's inheriting from the Point class? How does typing x,y for a point makes sense?

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

In the video example, he's passing the arguments that came in to the constructor along to the base. But here, the argument to Square is the length of the sides, but the base constructor is expecting the number of sides (which we know is 4 since it's a square).

Steve Perry
Steve Perry
8,739 Points
Steve Perry
Steve Perry
8,739 Points

Steven Parker wow, thanks so much that literally helped a ton!!! I appreciate it!