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C# C# Basics (Retired) Perfect Final

I get this error message:'System.ArgumentNullException: Value cannot be null. Parameter name: String. See output for sta

What is wrong with the code?

Program.cs
using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {
            bool notCorrectInput = true;
            int numberTimes;
            while (notCorrectInput)
            {
                try
                {
                    Console.Write("Enter the number of times to print \"Yay!\": ");
                    string numTimes = Console.ReadLine();
                    numberTimes = int.Parse(numTimes);
                    int counter = 0;
                    while (counter < numberTimes)
                    {
                        Console.WriteLine("\"Yay!\"");
                        counter += 1;
                    }

                }
                catch (FormatException)
                {
                    Console.WriteLine("You must enter a whole number.");
                    continue;
                }
                notCorrectInput = false;
            }
        }
    }
}

2 Answers

Steven Parker
Steven Parker
216,166 Points

I've answered this one before, for example in "C# Basics, Final Challenge, Task 2 of 3". Well, anyway, here it is again:

People often over-think this one and get too creative, and their answer is rejected for a variety of reasons (some which don't seem to make any sense).

Here are the secret "rules" you must follow for success on this one:

  • Your program must ask for and accept input ONE TIME ONLY
  • If the input validates, your program will perform exactly as in Task 1
  • If the input does not validate, it will print the error message and exit
  • Validation must be done by exception catching. There are other perfectly good methods that can be used for validation, but they will not pass this challenge

It looks like you have a loop that violates rule 1 and 3. Just remove the loop.

Christian Barahona
Christian Barahona
1,354 Points

Thank you for the clarification!!!

Thank you very much! I learned a lot from making the mistakes and in making my code simpler. Bernt