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C# C# Basics (Retired) Perfect Variable Scope

Posted by Kiem Ruach
Kiem Ruach
Courses Plus Student 2,520 Points

Variable scope

This code gives me an error saying that the variables are undefined, but I just don't see the problem. If you could explain it to me I'd appreciate it.

Program.cs 
using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {            
            input = Console.ReadLine();

            if (input == "quit")
            {
                string output = "Goodbye.";
            }
            else
            {
                string output = "You entered " + input + ".";
            }

            Console.WriteLine(output);
        }
    }
}

3 Answers

John Paige
John Paige
7,436 Points
John Paige
John Paige
7,436 Points

Passing code below!

using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {            
            string input = Console.ReadLine();

            if (input == "quit")
            {
                Console.WriteLine("Goodbye.");
            }
            else
            {
                Console.WriteLine("You entered " + input + ".");
            }

          //  Console.WriteLine(output);
        }
    }
}

You'll notice that 3 different lines were revised. Also, i commented out the last "Console.WriteLine" syntax to illustrate that it's not a necessary line of code. Hopefully this will help clarify the concepts, and that my input an be retained.

Kiem Ruach
PLUS
Kiem Ruach
Courses Plus Student 2,520 Points
Kiem Ruach
Kiem Ruach
Courses Plus Student 2,520 Points

thanks I bopped my head when i saw your reply this is actually very basic i got it and im past it now

John Paige
John Paige
7,436 Points
John Paige
John Paige
7,436 Points

It almost got me too. I know exactly how that was. I only figured it out because i had my workspace open alongside this challenge and i noticed the inconsistency.

John Paige
John Paige
7,436 Points
John Paige
John Paige
7,436 Points

Hello Kiem Ruach. I hope my answer will help you. I'll post my passing code in a different post in case you'd prefer to just use a hint.

What the challenge objective is asking you to do is change the syntax so that it compiles. You don't actually have to change the variable scope. For example:

static void Main()
        {            
            input = Console.ReadLine();
/*On the line above, do you notice that there is a missing type?

 The word "input" needs to be set up as a string.*/
            if (input == "quit")
            {
                string output = "Goodbye.";
            }
            else  /*where you see "output", the desired function is to Write something out
 to the Console. */
            {
                string output = "You entered " + input + ".";
            }

            Console.WriteLine(output);
        }

I'll post my passing syntax in my next post.