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C# C# Basics (Retired) Perfect Variable Scope

Posted by Moad Wakif
Moad Wakif
Courses Plus Student 835 Points

i didn t find a solution

string input = Console.ReadLine(); string output = "";

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

        Console.WriteLine(output);
    }
Program.cs 
using System;

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


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

            Console.WriteLine(output);
        }
    }
}

2 Answers

Brendan Whiting
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,738 Points
Brendan Whiting
.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,738 Points

The problem is the variable is declared inside the if block, and then we're trying to access it outside of that block which is out of scope. The challenge wants us to declare the variable earlier, before we open the if block, so that it's in an outer scope. I'm declaring it on line 4, and then later on line 8 I reassign the value with output = "Goodbye." as opposed to declaring it for the first time with string output = "Goodbye":

static void Main()
        {            
            string input = Console.ReadLine();
            string output;

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

            Console.WriteLine(output);
        }
Moad Wakif
PLUS
Moad Wakif
Courses Plus Student 835 Points
Moad Wakif
Moad Wakif
Courses Plus Student 835 Points

Thank you so much brother i understand you now