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C# C# Basics (Retired) Perfect Final

Posted by Nikolas Clay
Nikolas Clay
915 Points

Fixing an ArgumentNullException error

I originally received a compiler error stating there is a ArgumentNullException error in my String parameter. I attempted to resolve this error by adding a second "catch" clause. However, when I check my work again it errors out but time time with no explanation. So now I'm not sure what is wrong with my code.

Program.cs 
using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {
            Console.Write("Enter the number of times to print \"Yay!\": ");
            int timesToPrint = 0;
            while(true)
            {
                var countString = Console.ReadLine();
                try 
                {
                    timesToPrint = int.Parse(countString);

                    if(timesToPrint < 0)
                        Console.WriteLine("You entered a negative value.");

                    // Print Yay!
                    while(timesToPrint > 0)
                    {
                        Console.WriteLine("Yay" + " ");
                        timesToPrint--;
                    }
                    break;
                }
                catch(FormatException)
                {
                    Console.WriteLine("You must enter a whole number.");
                    continue;
                }
                catch(ArgumentNullException)
                {
                    Console.WriteLine("You must enter a response.");
                    continue;
                }
            }   

        }
    }
}

1 Answer

Steven Parker
Steven Parker
231,108 Points
Steven Parker
Steven Parker
231,108 Points

It looks like you have an extra loop.

This challenge only needs one loop to print out the right number of "Yay!" messages. It looks like you have an extra outer loop that's not needed and causing the program to require input more than once.

Also, remember the exclamation point in "Yay!".