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C# C# Basics (Retired) Perfect Final

Input Validation

Can someone help me out with my code. Its asking for input validation for a negative number input.

Program.cs
using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {
            try
            {
                Console.Write("Enter the number of times to print \"Yay!\": ");
                string input = Console.ReadLine();
                int input2 = int.Parse(input);

                while (input2 > 0)
                {
                    if (input2 != 0)
                    {
                        input2 -= 1;
                        Console.WriteLine("Yay!");
                    }
                    else
                    {
                        break;
                    }
                }
            }
            catch (FormatException)
            {
                Console.WriteLine("you must enter a whole number");
            }
            catch
            {
                Console.WriteLine("you must enter a positive number");
            }
        }
    }
}

1 Answer

Steven Parker
Steven Parker
231,236 Points

You don't need a catch to check for a negative input.

You can do this easily after you have parsed the input into a number. Then you can test the number in an if statement to see if it is negative, and if so give the feedback and end the program.

Also, you don't need that if inside the while, because the loop condition itself is enough to cause the loop to stop.