c# - How to compare these two strings representing a file name -

i want compare 2 strings represent file name:

private void button2_click(object sender, eventargs e) {     string search = textbox1.text;     string[] files = directory.getfiles(@"c:\cache", "*.*", searchoption.alldirectories);     int flag = 0;     string dir = @"c:\cache";     string[] files1;     int numfiles;     files1 = directory.getfiles(dir);     numfiles = files.length;      messagebox.show("files searched : " + numfiles);     console.writeline("files searched : " + numfiles + "<br>");     foreach (string name in files1)     {        if (textbox1.text.substring(23,30) == files1.tostring()) // << line        {            messagebox.show(name);        }    } } 

i have question how that, comparing using line:

if (textbox1.text.substring(23,30) == files1.tostring()) 

where

textbox1 = "http://localhost:11806/ourwork.html"  files1   = "d:\m.tech\dissertation 2\cache\ourwork.html" 

it have put codes run search on file cache or directory on machine.

    private void button2_click(object sender, eventargs e) {     {         list<string> searchresults = searchcache(textbox1.text, @"c:\cache");          foreach (string file in searchresults)         {             //messagebox popup can set here if like...             console.writeline(string.format("found: {0}", file));         }     }      /// <summary>     /// finds matches file name in search text     /// </summary>     /// <param name="searchtext">the file path in search text</param>     /// <param name="cachepath">the cache path</param>     /// <returns></returns>     private list<string> searchcache(string searchtext, string cachepath)     {         string[] files = directory.getfiles(cachepath, "*.*", searchoption.alldirectories);          console.writeline(string.format("no. of files in cache: {0}", files.length));          list<string> searchresults = new list<string>();          foreach (string file in files)             if (arefilereferencessame(searchtext, file))                 searchresults.add(file);          console.writeline(string.format("no. of matches: {0}", searchresults.count));          return searchresults;     }      /// <summary>     /// checks if files referenced url , cache versions same     /// </summary>     /// <param name="url">url path</param>     /// <param name="filepath">cached file full path</param>     /// <returns></returns>     private bool arefilereferencessame(string url, string filepath)     {         //extract file names both strings         int lastindexofurl = url.lastindexof("/");         int lastindexofpath = filepath.lastindexof(@"\");          //move marker 1 ahead if placeholders found         lastindexofurl = lastindexofurl >= 0 ? lastindexofurl + 1 : 0;         lastindexofpath = lastindexofpath >= 0 ? lastindexofpath + 1 : 0;          string urlfilename = url.substring(lastindexofurl).trim();         string diskfilename = filepath.substring(lastindexofpath).tostring();          if (urlfilename.equals(diskfilename, stringcomparison.currentcultureignorecase))             return true;         else             return false;     } }