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C# C# Basics (Retired) Perfect Final

Shing wai Chan
Shing wai Chan
1,255 Points
Posted by Shing wai Chan
Shing wai Chan
1,255 Points

I don't know what cause the exception i get

i get System.NullReferenceException: Object reference not set to an instance of an object. but i can't finde it. i have commet some code out, but they make no difference.

Program.cs 
using System;
namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {
          int total = 0;
          int counter = 0;          
          while (true)
          {
            Console.Write("Enter the number of times to print \"Yay!\": ");            
            var user = Console.ReadLine();
            if ( user.ToLower()== "quit")
            { break;}

            // try
            //{
              int numberOfTime = int.Parse(user);            
              while( counter < numberOfTime)
              {
                Console.Write("\"Yay!\": ");
                counter++;
              } 
               counter = 0;
               total += numberOfTime;
              Console.WriteLine("\n"+ "Numbers of Yay enter:"+ total);           
           // }
            //catch (FormatException)
            //{              
             // Console.WriteLine("This is not a number");
             //continue;
            //}   
          }
        }
    }
}

1 Answer

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

Here are a few hints for passing this challenge:

  • Your program must ask for and accept input ONE TIME ONLY (no loop around input)
  • 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. Your Parse must be inside a try block.
Shing wai Chan
Shing wai Chan
1,255 Points
Shing wai Chan
Shing wai Chan
1,255 Points

ahh, i got it! thanks for the explanation :)