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C# Intermediate C# Abstraction Interfaces

Adam Gothmann
Adam Gothmann
4,679 Points
Posted by Adam Gothmann
Adam Gothmann
4,679 Points

C# interfaces - stuck on defining the class

My code seems correct, but when i try and check my work it says "Did you define a Treehouse.CodeChallenges.Increment class?". What exactly is wrong with my class definition? I have tried using abstract, taking away public, pretty much any option that i have and it doesn't work.

IUnaryOperation.cs 
namespace Treehouse.CodeChallenges
{
    interface IUnaryOperation
    {
        double Perform(double value);
    }
}
Increment.cs 
namespace Treehouse.CodeChallenges
{
    public class Increment : IUnaryOperation
    {
        public double Perform(double value)
        {
            return value++;
        }
    }
}

1 Answer

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

You've almost got it.

But .. by using the unary postfix increment operator ("value++"), you are returning the value prior to incrementing it.

Try incrementing with the prefix operator ("++value") or with "value += 1" instead.