Decimal To Hexa loops only

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

namespace _16.DecimalToHexadecimal
{
    class DecimalToHexadecimal
    {
        static void Main()
        {
            Console.Write("Enter a number to convert in hexadecimal: ");
            long dec = long.Parse(Console.ReadLine());
            long result = 0;
            string hexResult = string.Empty;
            for (long i = dec; i >= 1 ; i /= 16)
            {
                result = i % 16;
                string hex = string.Empty;

                switch (result)
                {
                    case 10:
                        hex = "A" + hex;
                        break;
                    case 11:
                        hex = "B" + hex;
                        break;
                    case 12:
                        hex = "C" + hex;
                        break;
                    case 13:
                        hex = "D" + hex;
                        break;
                    case 14:
                        hex = "E" + hex;
                        break;
                    case 15:
                        hex = "F" + hex;
                        break;
                    default:
                        hex = hex + result;
                        break;
                }
                hexResult += hex;
            }
            Console.WriteLine(hexResult.Reverse().ToArray());
        }
    }
}