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C# C# Objects Encapsulation with Properties Expression Bodied Members

Tojo Alex
PLUS
Tojo Alex
Courses Plus Student 13,331 Points

I have an error though I don't understand what it is

The compiler error is this: Square.cs(7,42): error CS1061: Type double' does not contain a definition forGetLocationAt' and no extension method GetLocationAt' of typedouble' could be found. Are you missing an assembly reference? /usr/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error) Compilation failed: 1 error(s), 0 warnings Forget about the Polygon.cs script.

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

        public double Area => SideLength.GetLocationAt(SideLength);

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

        public void Scale(double factor)
        {
            SideLength *= factor;
        }
    }
}
Polygon.cs
namespace Treehouse.CodeChallenges
{
    class Polygon
    {
        public int NumSides { get; private set; }

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

2 Answers

Steven Parker
Steven Parker
231,198 Points

The compiler is giving you a good hint. A "double" has no method named "GetLocationAt". I'm wondering where you got that from since it's not mentioned in the instructions or provided in the original code!

Your single line-version of the computed property should only do the same thing that the original one did. The only change should be to the definition syntax.

Tojo Alex
Tojo Alex
Courses Plus Student 13,331 Points

I got GetLocationAt from the video it is just stuck in my mind I fixed the error now thanks.

Steven Parker
Steven Parker
231,198 Points

One thing you can rely on about the challenges is that they will cover the video concepts, but they will never be an exact repeat of the video examples.