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C# C# Basics (Retired) Perfect Final

Giannis Kataras
Giannis Kataras
1,279 Points
Posted by Giannis Kataras
Giannis Kataras
1,279 Points

Stuck in last challenge

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 () [0x00010] in <127eb559eb9944a6ad1a80cc101f8094>:0 at MonoTester.Run () [0x00208] in /workdir/MonoTester.cs:140

I get this error code what is the fault in my code?

Program.cs 
using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {
         while(true)
         {

            Console.Write("Enter the number of times to print \"Yay!\": ");
           string input=Console.ReadLine();


            try
            { var number = int.Parse(input);
             while (number!=0)
             { Console.WriteLine("Yay");
             number-=1;}
            if (number==0)
            {break;}
        }
        catch (FormatException)

        { Console.WriteLine("you must enter a whole number");
        continue;}
        } 
        }


    }
}

3 Answers

David Tomko
David Tomko
7,744 Points
David Tomko
David Tomko
7,744 Points

Sorry in advance for the sloppy written code...

using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {

        static void Main()
        {
            try{

            Console.Write("Enter the number of times to print \"Yay!\": ");
            string numberOfTimes = Console.ReadLine();
            int i = 0;
            if(int.Parse(numberOfTimes) >= 0){    
            while(i < int.Parse(numberOfTimes))
            {
             Console.Write("Yay");
                i++;
            }

            }
                else{
               Console.WriteLine("You must enter a positive number."); 
            }
            }
            catch(FormatException){
             Console.WriteLine("You must enter a whole number.");   
            }

        }
    }
}
Giannis Kataras
Giannis Kataras
1,279 Points
Giannis Kataras
Giannis Kataras
1,279 Points

Thanks for the answer, but this part of code its a bit tricky to understand can you explain me :
while(i < int.Parse(numberOfTimes)) { Console.Write("Yay"); i++; } Thanks a lot!

David Tomko
David Tomko
7,744 Points
David Tomko
David Tomko
7,744 Points

Okay so this is saying while i (which is just a counter for the while loop) is less than numberOfTimes(but here we are Parsing the data type from a string to an int so we can compare it with our other int value aka the counter 'i' because you can't compare mismatching data types) print "YAY" then add 1 to i. I hope this helped if not lmk.