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C# C# Objects Encapsulation with Properties Computed Properties

Erik Luo
Erik Luo
3,810 Points

How do you do this?

How do you return the area?

Square.cs
namespace Treehouse.CodeChallenges
{
    class Square : Polygon
    {
        public double SideLength { get; private set; }

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

        public double Area 
        {
            get
            {
            return double Square * double Square;
            }
        }
    }
}
Polygon.cs
namespace Treehouse.CodeChallenges
{
    public class Polygon
    {
        public int NumSides { get; private set; }

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

1 Answer

Steven Parker
Steven Parker
230,325 Points

:point_right: It looks like you have the right general idea.

But you don't want to declare the types of the operands in your calculation expression. And you probably also want to calculate using the SideLength property instead of the class itself.

Erik Luo
Erik Luo
3,810 Points

So how do you do this? Do I make another variable put the calculation in it and then get it in the area? I tried it and it doesn't work. Can you explain more?

Erik Luo
Erik Luo
3,810 Points

It asks for the area of the square, it has sidelength of 4. If I use the SideLength property, will it give me the area of the square?

Erik Luo
Erik Luo
3,810 Points

I got it, I moved public double Area { get { return SideLength * SideLength; } } before Square instead after.