正在从字符串中筛选文本

我现在有这样的：

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using System.Threading.Tasks;
namespace ConsoleApplication2
{
   public class Program
    {
        static void Main(string[] args)
        {
            //Consider making this configurable
            const string sourceFile = "test2.txt";
            const string pattern = "http://10.123.9.66:80";
            //var FirstSeparatorLastNameExact = new[] { "nosyn_name_last_exact:(qxq" };
            //var SecondSeparatorLastNameExact = new[] { "qxq)" };
            string[] FirstSeparator = new string[] { "nosyn_name_last_exact:(qxq" };
            string[] SecondSeparator = new string[] { "qxq)" };
            string[] FirstSeperatorFirstName = new string[] {"nosyn_name_first_exact:(qxq"};
            string[] secondSeperatorFirstName = new string[]{"qxq)"};

            Regex re = new Regex("^(http|https)://");
            HttpWebResponse response;
           // var webClient = new WebClient();
            var times = new Dictionary<string, TimeSpan>();
            var stopwatch = new System.Diagnostics.Stopwatch();
            //Add header so if headers are tracked, it will show it is your application rather than something ambiguous
            //webClient.Headers.Add(HttpRequestHeader.UserAgent, "Response-Tester-Client");
            var urlList = new List<string>();
            //Loop through the lines in the file to get the urls 
            try
            {
                stopwatch.Start();
                using (var reader = new StreamReader(sourceFile))
                {
                    while (!reader.EndOfStream)
                    {
                        var urNewList = new List<string>();
                        var line = reader.ReadLine();
                        //line = line.Substring(line.IndexOf(pattern));
                        //line.Split("'t");
                        var columns = line.Split(''t');
                        //var result = line.Split(Seperator, StringSplitOptions.RemoveEmptyEntries)[1].Split(')')[0];
                        if (columns[2] == "R")
                        {
                            var url = columns[4] + "?" + columns[5];
                            urlList.Add(url);
                            Thread.Sleep(250);
                        }
                        //if (line.Contains(result))
                        //{
                            //MatchCollection matches = Regex.Matches(line, lastName);
                            //foreach (string lines in File.ReadLines(sourceFile))
                            //{
                                //var LastNameSearch = line.Split(FirstSeparatorLastNameExact, StringSplitOptions.RemoveEmptyEntries)[1];
                                //var resultLastNameSearch = LastNameSearch.Split(FirstSeparatorLastNameExact, StringSplitOptions.RemoveEmptyEntries)[0];

                                //var temp = line.Split(FirstSeparator, StringSplitOptions.RemoveEmptyEntries)[1];
                                //var result2 = temp.Split(SecondSeparator, StringSplitOptions.RemoveEmptyEntries)[0];
                                //Console.WriteLine(result2);
                        string[] result = line.Split(FirstSeperatorFirstName, StringSplitOptions.RemoveEmptyEntries);
                        if (result.Length > 2)
                        {
                            string[] inner = result[1].Split(')');
                            if (inner.Length > 1)
                            {
                                Console.WriteLine(inner[0]);
                                Console.WriteLine(result);
                            }
                        }

                        //var split = line.Split(FirstSeperatorFirstName, StringSplitOptions.RemoveEmptyEntries);
                        //if (split.Length > 1)
                        //{
                        //    Console.WriteLine(split[1].Split(')')[0]);
                        //   // Console.WriteLine(split);
                        //}

                    }
                }
            }
            catch (Exception e)
            {
                Console.WriteLine("An error occured while attempting to access the source file at {0}", sourceFile);
            }
            finally
            {
                //Stop, record and reset the stopwatch
                stopwatch.Stop();
                times.Add("FileReadTime", stopwatch.Elapsed);
                stopwatch.Reset();
            }
            //Try to connect to each url
            var counter = 1;
            foreach (var url in urlList)
            {
                try
                {
                    stopwatch.Start();
                    using (WebClient webClient = new WebClient())
                    {
                        webClient.Headers.Add(HttpRequestHeader.UserAgent, "Response-Tester-Client");
                       // HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
                        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
                        request.Method = "POST";
                        //webClient.Dispose();
                    }
                }
                catch (Exception e)
                {
                    Console.WriteLine("An error occured while attempting to connect to {0}", url);
                }
                finally
                {
                    stopwatch.Stop();
                    //We use the counter for a friendlier url as the current ones are unwieldly
                    times.Add("Url " + counter, stopwatch.Elapsed);
                    counter++;
                    stopwatch.Reset();
                }
            }
            //Release the resources for the WebClient 
            //webClient.Dispose();
            //Write the response times
            Console.WriteLine("Url " + "'t't't'tLast Name");
            foreach (var key in times.Keys)
            {
                Console.WriteLine("{0}: {1}", key, times[key].TotalSeconds);
            }

            Console.ReadKey();
        }
    }
}

但我仍然得到错误：索引超出了数组的界限。那么如何改变呢？事实上，它还必须去掉qxq。我用我在上声明的两个字符串来尝试

感谢