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C# Querying With LINQ Functional Programming in C# LINQ Method Syntax

Daniel Hildreth
Daniel Hildreth
16,170 Points
Posted by Daniel Hildreth
Daniel Hildreth
16,170 Points

LINQ method syntax challenge 2 help

I do not know what property name I am supposed to pass into this argument. In the video we had colors and names. In this there is the list of numbers. Can someone help explain what I'm missing in my code?

I have tried the following lines of code. But I do not know what I'm missing. 

return _numbers.OrderByDescending((n) => n.NumbersGreaterThanFive);
return _numbers.OrderByDescending((n) => n.numbersGreaterThanFive);
return _numbers.OrderByDescending((n) => n.List);
return _numbers.OrderByDescending((n) => n._numbers);
NumberAnalysis.cs 
using System.Collections.Generic;
using System.Linq;

namespace Treehouse.CodeChallenges
{
    public class NumberAnalysis
    {
        private List<int> _numbers;
        public NumberAnalysis()
        {
            _numbers = new List<int> { 2, 4, 6, 8, 10 };
        }

        public IEnumerable<int> NumbersGreaterThanFive()
        {
            return _numbers.Where((n) => n > 5);
        }

        public IEnumerable<int> ReverseNumbers()
        {
            return _numbers.OrderByDescending((n) => n.);
        }
    }
}

1 Answer

Steven Parker
Steven Parker
231,072 Points
Steven Parker
Steven Parker
231,072 Points

:point_right: Your lambda expression has a stray period (.) at the end.

A period would either separate the integer and fractional components of a literal float or double, or would be a membership operator and be followed by a member name (neither applies in this case).

:information_source: Also, while it does not cause a problem, you don't need parentheses around a single parameter in a lambda expression.

Daniel Hildreth
Daniel Hildreth
16,170 Points
Daniel Hildreth
Daniel Hildreth
16,170 Points

Thanks Steven. Was not fully aware I didn't have to pass it anything.