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C#

Unable to finish C# Basics Final Code Challenge

This is the Code Challenge: https://teamtreehouse.com/library/c-basics/perfect/final My code is as follows:

using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {
            while(true)
            {
                int timesRan = 0;
                Console.Write("Enter the number of times to print \"Yay!\": ");
                string entry = Console.ReadLine();
                try
                {
                    int times = int.Parse(entry);
                    while(timesRan < times)
                    {
                        Console.WriteLine("\"Yay!\"");
                        timesRan += 1;
                    }
                    break;
                }
                catch (FormatException)
                {
                    Console.WriteLine("You must enter a whole number.");
                    continue;
                }
            }
        }
    }
}

It successfully got me through step 1 and while it should pass step 2 as well, it does not. I know it should because it worked when I tried it in a Treehouse Workspace. The result in the Workspace was a FormatException, as expected, but the Code Challenge itself returned an ArgumentNullException seen below.

Bummer! System.ArgumentNullException: Value cannot be null. Parameter name: String at System.Number.StringToNumber (System.String str, System.Globalization.NumberStyles options, System.Number+NumberBuffer& number, System.Globalization.NumberFormatInfo info, System.Boolean parseDecimal) [0x00054] in /builddir/build/BUILD/mono-4.8.1/mcs/class/referencesource/mscorlib/system/number.cs:1074 at System.Number.ParseInt32 (System.String s, System.Globalization.NumberStyles style, System.Globalization.NumberFormatInfo info) [0x00014] in /builddir/build/BUILD/mono-4.8.1/mcs/class/referencesource/mscorlib/system/number.cs:745 at System.Int32.Parse (System.String s) [0x00000] in /builddir/build/BUILD/mono-4.8.1/mcs/class/referencesource/mscorlib/system/int32.cs:120 at Treehouse.CodeChallenges.Program.Main () [0x00012] in <f437b8f53cd1432eb8d9002d5e45d560>:0 at MonoTester.Run () [0x00208] in /workdir/MonoTester.cs:140

Any help that can be offered is appreciated.

1 Answer

Steven Parker
Steven Parker
231,261 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 if bad values are entered..

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.

Thank you Steven. I took out the extra loop and it worked so I will be sure to watch out for differences in REPL / IDE from now on.