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C# C# Basics (Retired) Perfect Variable Scope

Tojo Alex
PLUS
Tojo Alex
Courses Plus Student 13,331 Points
Posted by Tojo Alex
Tojo Alex
Courses Plus Student 13,331 Points

I don't understand what i'm doing here

In this code challenge i didn't fully understand the second step of what its asking me to do I keep on getting the same error : Did you remove the 'output' variable? Instead of removing the 'output' variable, try correcting the problem by changing the scope of the variable.

Program.cs 
using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {            
            string input = Console.ReadLine();
            string output = Console.WriteLine();
            if (input == "quit")
            {
                string 
            }
            else
            {
                string output = "You entered " + input + ".";
            }

            Console.WriteLine(output);
        }
    }
}

4 Answers

Robert Anthony
Robert Anthony
19,952 Points
Robert Anthony
Robert Anthony
19,952 Points

This is to do with the scoping of variables. A variable in C# only exists in the block of code { surrounded by curly brackets } in which is was declared. As the original code declared 'output' inside the if statement, once in each part, if either pieces of code executes, the variable 'output' will not exist by the time you get to the Console.WriteLine.

Remove the two 'string' keywords within the if statement. This will mean the output variable is modified with a new value rather than being declared again.

Modify your declaration to say:

string output="";

This will declare a variable called output, set it to an empty string ("") and make it available for the whole method.

Tojo Alex
Tojo Alex
Courses Plus Student 13,331 Points
Tojo Alex
Tojo Alex
Courses Plus Student 13,331 Points

could you show your code so i can see what i'm doing wrong in my code

Tojo Alex
PLUS
Tojo Alex
Courses Plus Student 13,331 Points
Tojo Alex
Tojo Alex
Courses Plus Student 13,331 Points

thanks for your help i understand now though it still shows the same error

Robert Anthony
Robert Anthony
19,952 Points
Robert Anthony
Robert Anthony
19,952 Points 
using System;

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

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

            Console.WriteLine(output);
        }
    }
}