Text-Based Calculator Made in C#.

using System;
using System.Threading;
using System.Text;
using System.Runtime;
using System.Media;
using System.IO;
using System.Net;

namespace Simple_Calculator
{
    class Calc
    {

        public static String num1String;
        public static String num2String;
        public static double num1;
        public static double num2;
        public static String oper;
        public static String response;

        public static void Main (string[] args)
        {

            if (args [0] == "-operators") {

                Console.WriteLine ("OPERATORS");
                Console.WriteLine ("\"+\" - add");
                Console.WriteLine ("\"-\" - subtract");
                Console.WriteLine ("\"*\" - multiply");
                Console.WriteLine ("\"/\" - divide");
                Console.WriteLine ("\"sin\" - calculate sine (if you use this operator, the second number does not count.)");
                Console.WriteLine ("\"cos\" - calculate cosine (if you use this operator, the second number does not count.)");
                Console.WriteLine ("\"%\" - calculate modulo (if you use this operator, the second number does not count.)");
                Console.WriteLine ("\"log\" - calculate logarithmic math");
                Console.WriteLine ("\"exp\" - calculate exponents");
                Console.WriteLine ("\"tan\" - calculate tangents (if you use this operator, the second number does not count.)");

            }

            Console.WriteLine ("Simple Text-Based Calculator by Aaron Murphy");
            Console.Write ("First Number>> ");
            num1String = Console.ReadLine ();

            num1 = Convert.ToInt32 (num1String);
            Console.WriteLine ("");

            Console.Write ("Second Number>> ");
            num2String = Console.ReadLine ();

            num2 = Convert.ToInt32 (num2String);
            Console.WriteLine ("");

            Console.Write ("Operator(+, -, *, /, sin, cos, %, log, exp, and tan)>> ");
            oper = Console.ReadLine ();
            Console.WriteLine ("");

            if (oper == "+") {

                Console.WriteLine (num1 + " + " + num2 + " = " + (num1 + num2));

            } else if (oper == "-") {

                Console.WriteLine (num1 + " - " + num2 + " = " + (num1 - num2));

            } else if (oper == "*") {

                Console.WriteLine (num1 + " * " + num2 + " = " + (num1 * num2));

            } else if (oper == "/") {

                Console.WriteLine (num1 + " / " + num2 + " = " + (num1 / num2));

            } else if (oper == "sin") {

                Console.WriteLine ("Sin(" + num1 + ") = " + Math.Sin (num1));

            } else if (oper == "cos") {

                Console.WriteLine ("");

            } else if (oper == "%") {



            } else if (oper == "log") {



            } else if (oper == "exp") {



            } else if (oper == "tan") {



            }

            Console.WriteLine ("");
            Console.Write ("Do you want to perform a new calculation(Y/N)?>> ");
            response = Console.ReadLine ();

            if (response == "Y" || response == "y") { //It works if the user types "Y" or "y".

                Console.WriteLine ("");
                Main (null);

            }

        }
    }
}