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C# C# Basics (Retired) Perfect Final

Posted by Nathan Yebgui
Nathan Yebgui
15,732 Points

Bummer! System.ArgumentNullException: Value cannot be null. Parameter name: String. See output for stack trace.

works fine in compiler. what have i missed?

Program.cs 
using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {
            Console.Write("Enter the number of times to print \"Yay!\": ");
            int N=0;

            while(true)
            {
            try
            {
                var entry = Console.ReadLine();
                N =  int.Parse(entry);

                break;
            }
            catch(FormatException)
            {
                Console.WriteLine("You must enter a whole number.");
                continue;
            }
            }
              while(N>0)
                {
                    Console.WriteLine("Yay!");
                    N--;
                }

        }
    }
}

1 Answer

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

:warning: Be careful about testing a challenge in an external REPL or IDE.

If you have misunderstood the challenge, it's also very likely that you will misinterpret the results.

In this case, you have added an extra loop that prevents the program from ending..

A program that follows the challenge instructions will only ask for input one time, and either print "Yay!"s or an error message. But either way it should end.

Nathan Yebgui
Nathan Yebgui
15,732 Points

Thanks, i removed the while(true) loop containing the try/catch and the code worked fine.