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C# Intermediate C# Abstraction Interfaces

Benson Gathee
PLUS
Benson Gathee
Courses Plus Student 1,280 Points
Posted by Benson Gathee
Benson Gathee
Courses Plus Student 1,280 Points

Does Increment have a constructor that takes no parameters? What is this error?

In Increment.cs create a class named Increment that implements the IUnaryOperation interface. The Perform method should increment the value passed in by one.

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

        public double Perform(double value) 
        {
            return value+=1;
        }

    }
}

1 Answer

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

That message is perhaps a bit misleading. The constructor is not the issue.

But the instructions did not say anything about creating an abstract class. Abstract classes cannot be instantiated, which is most likely how the challenge tests the code.