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C# C# Basics (Retired) Perfect Variable Scope

Joel Muro
Joel Muro
2,884 Points
Posted by Joel Muro
Joel Muro
2,884 Points

try code and catch exceptions

Fix the code so that it compiles, but don't change the intent of the code.

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);
    }
}

}

i have no idea where to start?

2 Answers

Steven Parker
Steven Parker
231,235 Points
Steven Parker
Steven Parker
231,235 Points

Assuming you'd like hints, and not just the answer:

  • This challenge is about declaration and scope.
  • Look carefully at where (and if!) the variables are declared
  • Consider the error messages generated from the compiler.
  • Each variable should have one declaration.
  • If you see a variable being declared more than once, it probably needs to be declared once in a wider scope.

Another hint: there is more than one thing that must be fixed for this code to compile.

Joel Muro
Joel Muro
2,884 Points
Joel Muro
Joel Muro
2,884 Points

I see that there are 2 string output = but to different text. is that going in the right direction?

Steven Parker
Steven Parker
231,235 Points
Steven Parker
Steven Parker
231,235 Points

Good catch. This is a case where you want to move the declaration to a wider scope and convert the declarations/assignments into simple assignments. So instead of:

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

You might have:

        string output = "";  // <-- empty assignment to appease the compiler
        if (input == "quit")
        {
            output = "Goodbye.";  // <-- just a plain assignment
        }
        else
        {
            output = "You entered " + input + ".";  // <-- also just a plain assignment
        }

...or perhaps eliminate the else entirely (this is a bit more than just fixing it to compile):

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