progzh2.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace IziProgZH2
{
    internal class Program
    {
        internal const string cuser = "gipszjakab";
        internal const string cpasswd = "alma";

        internal static void Main(string[] args)
        {
            string user = "";
            string pw = "";
            string pick = "";
            Console.WriteLine("Login with ur username/password");
            Console.WriteLine("User: ");
            user = Console.ReadLine();
            Console.WriteLine("Pw: ");
            pw = Console.ReadLine();
            while (user.ToLower() != cuser && pw.ToLower() != cpasswd)
            {
                Console.WriteLine("Invalid login data!");
                Console.WriteLine("User: ");
                user = Console.ReadLine();
                Console.WriteLine("Password: ");
                pw = Console.ReadLine();
            }
            Console.WriteLine("Successfully logged in! Type kör or négyzet");

            pick = Console.ReadLine();
            while (pick.ToLower() != "kör" && pick.ToLower() != "négyzet")
            {
                Console.WriteLine("Invalidpick!");
                Console.WriteLine("Type 'kör' or 'négyzet'");
                pick = Console.ReadLine();
            }
            string svalue;
            double dv;
            if (pick == "kör")
            {
                Console.WriteLine("Type the desired r to calculate with:");
                svalue = Console.ReadLine();
                bool b = double.TryParse(svalue, out dv);
                while (!b)
                {
                    Console.WriteLine("Type the desired r to calculate with:");
                    svalue = Console.ReadLine();
                    b = double.TryParse(svalue, out dv);
                }
                Console.WriteLine("Calc: " + 3.14 * dv*dv);
            }
            else
            {
                Console.WriteLine("Type the desired a to calculate square's T with:");
                svalue = Console.ReadLine();
                bool b = double.TryParse(svalue, out dv);
                while (!b)
                {
                    Console.WriteLine("Type the desired r to calculate with:");
                    svalue = Console.ReadLine();
                    b = double.TryParse(svalue, out dv);
                }
                Console.WriteLine("Calc: " + dv*dv);
            }
            Console.ReadKey();
        }
    }
}