String to keycode and switch check, C#

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//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using System.Windows.Forms;

namespace Rextester
{
    public class Program
    {
        public static void Main(string[] args)
        {
            //Your code goes here

Console.WriteLine("Keys to code:");
            Console.WriteLine("+ = " + (int)'+');
            Console.WriteLine("- = " + (int)'-');
            Console.WriteLine("/ = " + (int)'/');
            Console.WriteLine("* = " + (int)'*');
            Console.WriteLine("---------------");
            
            var actionCode = "-".First();
            
            switch((int)actionCode)
            {
                    case 45:
                        Console.WriteLine("Dit is min");
                        break;
                    case 43:
                        Console.WriteLine("Dit is plus");
                        break;
                    default:
                        Console.WriteLine("Onbekend");
                        break;
            }
        }
    }
}

Show compiler warnings [ + ] Show input
Compilation time: 0,17 sec, absolute running time: 0,08 sec, cpu time: 0,08 sec, average memory usage: 12 Mb, average nr of threads: 3