UrlParser.cs

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


namespace UrlParser
{
    class Program
    {
        static void Main(string[] args)
        {
           
            string[] text = new string[25];
            string regexp;
            string hostname = "(not set)";
            string pagepath = "(not set)";

            text[10] = "http://www5.mysite.com/mypage/index.php";
            text[2] = "http://www5.mysite.com/mypage/index.php";
            text[8] = "http://www5.mysite.com/mypage/";
            text[7] = "//www.mysite.com/";
            text[6] = "//www.mysite.com/test/index.php";
            text[0] = "/mypage/";
            bool startsWithHttp = Regex.IsMatch(text[0], @"^http[s]{0,1}://");
            bool startsWithDoubleSlash =  Regex.IsMatch(text[0], @"^//");
            bool startsWithSingleSlash = Regex.IsMatch(text[0], @"^[/]{1}");
            
            
            if (startsWithHttp)
            {
                Console.WriteLine("Starts with http");
                Console.WriteLine(text[0]);
                regexp = @"^http[s]{0,1}://[w]{0,3}[0-9]{0,1}\.([\w]+\.[A-Za-z]{1,3})(/.+)$";
                Match m = Regex.Match(text[0], regexp, RegexOptions.CultureInvariant);
                hostname = m.Groups[1].Value;
                pagepath = m.Groups[2].Value;

            }

            if (startsWithDoubleSlash)
            {
                Console.WriteLine("Starts with double slash");
                Console.WriteLine(text[0]);
                regexp = @"^//[w]{0,3}[0-9]{0,1}\.([\w]+\.[A-Za-z]{1,3})((/.+)|(/))"; 
                Match m = Regex.Match(text[0], regexp, RegexOptions.CultureInvariant);
                hostname = m.Groups[1].Value;
                pagepath = m.Groups[2].Value;

            }
            if (startsWithSingleSlash)
            {
                Console.WriteLine("Starts with single slash");
                Console.WriteLine(text[0]);
                regexp = @"^(/.+)$";
                Match m = Regex.Match(text[0], regexp, RegexOptions.CultureInvariant);
                hostname = "- Invalid -";
                pagepath = m.Groups[1].Value;

            }

            Console.WriteLine("Hostname: {0}", hostname);
            Console.WriteLine("Page Path: {0}", pagepath);

            System.Console.Read();
        }
    }
}