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C# Intermediate C# Abstraction Interfaces

Posted by Brad Price
Brad Price
18,570 Points

i am not sure how to implement this interface

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

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

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

:point_right:When implementing an interface, you still follow the normal rules for methods:

  • methods defined inside the class should not be prefaced by the interface name
  • methods need a declared access (usually public)
  • methods need a declared return type (the same as the interface specification)
  • parameters need a declared type (the same as the interface specification)
  • the increment operator ("+=") needs the increment quantity on the right side