该名称在当前上下文中不存在

Question

In case 3: I wrote mutteer(ba, bb, bc, bd, be); which seems to give the error ( The name ba does not exist in current context ). It gives the same error with bb bc bd and be .

What did I do wrong?

I removed most of the unnecessary code:

static void menu()
    {
        int loop = 4;
        Console.WriteLine(" 3  Mutteer Voorraad");

        while (loop > 2)
            {
            var ans = Console.ReadLine();
            mp3();
            int choice = 0;
            if (int.TryParse(ans, out choice))
            {
                switch (choice)
                {
                    case 3:
                        Console.WriteLine("Mutteer Voorraad.");
                        mutteer(ba, bb,  bc, bd, be);
                        break;

                    default:
                        Console.WriteLine("Wrong selection!!!");
                        Thread.Sleep(1800);
                        Console.Clear();
                        goto top;
                }
            }
            else
            {
                Console.WriteLine("You must type numeric value only!!!");
                Thread.Sleep(1800);
                Console.Clear();
                goto top;
            }
        }
    }

static void mp3()
    {
        int ba = 500;
        int bb = 500;
        int bc = 500;
        int bd = 500;
        int be = 500;

        mp3players mp1 = new mp3players();
        mp1.id = 1;
        mp1.VR = ba;
     }

static void mutteer(int ba, int bb,  int bc, int bd, int be)
     {
        int i = 1;
        int a;

        startloop:
        while (i == 1)
            {
                Console.WriteLine("Wat is het Id van de mp3 speler?");
                try
                {
                    a = Convert.ToInt16(Console.ReadLine());
                }
                catch
                {
                    Console.WriteLine("Dat is geen nummer waarde!");
                    goto startloop;
                }

                if (a == 1)
                {
                    Console.WriteLine("Wat is het nieuwe voorraad");
                    try
                    {
                        i = 2;
                        ba = Convert.ToInt32(Console.ReadLine());
                    }
                    catch
                    {
                        Console.WriteLine("Dat is geen nummer waarde!");
                        goto startloop;
                    }
            }
        }

Answer 1

You need to move the declarations of ba and the other variables to the global scope. As the code is currently written, they're accessible only in the scope of the mp3 method. You should have:

static int ba = 500;
static int bb = 500;
static int bc = 500;
static int bd = 500;
static int be = 500;

  static void mp3()
    {
    mp3players mp1 = new mp3players();
    mp1.id = 1;
    mp1.VR = ba;
    }