Computed Properties

Question

I don't understand how computed properties work. I can't tell how they are different from methods because they look the exact same. I am supposed to code a computed property named Area that returns the area of the square, but every solution I have provided is rejected. Any pointers would be much appreciated.

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 SideLength * SideLength;
            }
        }
    }
}

Polygon.cs

namespace Treehouse.CodeChallenges
{
    public class Polygon
    {
        public int NumSides { get; private set; }

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

Answer 1 · 2017-08-24T16:15:37Z

August 24, 2017 4:15pm

Computed properties don't quite look like methods. Namely, since they will never take any parameters by definition, you don't use parentheses to define them or call them. You'll just use the get keyword with brackets, and put the code you need to compute its value between those brackets. It'd look something like this:

namespace Example
{
    class Triangle : Polygon
    {
        public double baseLength{ get; private set; }
        public double height{ get; private set; }
        public double Area{
            get{
                return 0.5 * baseLength * height;
            }
        }
    }
}

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Josh Boersma

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Computed Properties

1 Answer

Michael Hulet

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Josh Boersma

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Michael Hulet

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