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c#regexwpflogfile-analysis

Read a Log file and pull out lines with specific text


I have a log that is constantly being added to (like 1-5 lines a second or more) and the files can get rather large 20MB+

Example Log File:

[Wed Aug 26 00:01:48 2015] You try to kick a snake, but miss!
[Wed Aug 26 00:01:50 2015] A snake hits YOU for 3 points of damage.
[Wed Aug 26 00:01:51 2015] You punch a snake for 6 points of damage.
[Wed Aug 26 00:01:51 2015] A decaying skeleton tries to hit Clumsy, but misses!
[Wed Aug 26 00:01:53 2015] A snake hits YOU for 1 point of damage.
[Wed Aug 26 00:01:53 2015] A decaying skeleton tries to hit Clumsy, but misses!
[Wed Aug 26 00:01:54 2015] You gain experience!!
[Wed Aug 26 00:01:54 2015] You punch a snake for 6 points of damage.
[Wed Aug 26 00:01:54 2015] You have slain a snake!
[Wed Aug 26 00:01:56 2015] --You have looted a Snake Egg.--
[Wed Aug 26 00:01:56 2015] A decaying skeleton tries to hit Clumsy, but misses!
[Wed Aug 26 00:01:57 2015] --You have decided to not loot 2 item(s): Snake Fang. The item(s) will be available to anyone after the corpse(s) unlock.--
[Wed Aug 26 00:01:57 2015] --You have decided to not loot 2 item(s): Snake Scales. The item(s) will be available to anyone after the corpse(s) unlock.--
[Wed Aug 26 00:01:59 2015] a decaying skeleton's corpse splinters into hundreds of tiny bone fragments.
[Wed Aug 26 00:01:59 2015] Clumsy crushes a decaying skeleton for 7 points of damage.
[Wed Aug 26 00:01:59 2015] a decaying skeleton has been slain by Clumsy!
[Wed Aug 26 00:01:59 2015] Auto attack is on.
[Wed Aug 26 00:02:00 2015] Grug tells General:2, 'LFM AM/LORD'
[Wed Aug 26 00:02:00 2015] You punch a large rat for 5 points of damage.
[Wed Aug 26 00:02:00 2015] A large rat bites YOU for 1 point of damage.
[Wed Aug 26 00:02:00 2015] You kick a large rat for 1 point of damage.
[Wed Aug 26 00:02:02 2015] You punch a large rat for 2 points of damage.
[Wed Aug 26 00:02:03 2015] A large rat tries to bite YOU, but misses!
[Wed Aug 26 00:02:06 2015] You punch a large rat for 6 points of damage.
[Wed Aug 26 00:02:06 2015] A large rat bites YOU for 1 point of damage.
[Wed Aug 26 00:02:08 2015] a decaying skeleton clatters as it turns towards you.
[Wed Aug 26 00:02:08 2015] <SYSTEMWIDE_MESSAGE>: Gorenaire has been defeated by a group of hardy adventurers! Please join us in congratulating Kyrax along with everyone else who participated in this achievement!
[Wed Aug 26 00:02:08 2015] Clumsy tries to crush a decaying skeleton, but misses!
[Wed Aug 26 00:02:08 2015] A decaying skeleton tries to hit Clumsy, but misses!
[Wed Aug 26 00:02:09 2015] A large rat tries to bite YOU, but YOU dodge!
[Wed Aug 26 00:02:09 2015] You try to punch a large rat, but miss!
[Wed Aug 26 00:02:11 2015] Clumsy crushes a decaying skeleton for 8 points of damage.
[Wed Aug 26 00:02:11 2015] A decaying skeleton hits Clumsy for 2 points of damage.
[Wed Aug 26 00:02:11 2015] You kick a large rat for 1 point of damage.
[Wed Aug 26 00:02:12 2015] A large rat bites YOU for 1 point of damage.
[Wed Aug 26 00:02:13 2015] You gain experience!!
[Wed Aug 26 00:02:13 2015] You punch a large rat for 6 points of damage.
[Wed Aug 26 00:02:13 2015] You have slain a large rat!
[Wed Aug 26 00:02:13 2015] Clumsy crushes a decaying skeleton for 8 points of damage.
[Wed Aug 26 00:02:14 2015] A decaying skeleton hits Clumsy for 3 points of damage.
[Wed Aug 26 00:02:15 2015] --You have decided to not loot 1 item(s): Piece of Rat Fur. The item(s) will be available to anyone after the corpse(s) unlock.--
[Wed Aug 26 00:02:15 2015] --You have decided to not loot 2 item(s): Rat Whiskers. The item(s) will be available to anyone after the corpse(s) unlock.--
[Wed Aug 26 00:02:16 2015] a decaying skeleton's corpse splinters into hundreds of tiny bone fragments.
[Wed Aug 26 00:02:18 2015] Auto attack is on.
[Wed Aug 26 00:02:18 2015] a snake hisses and strikes!
[Wed Aug 26 00:02:18 2015] You punch a snake for 6 points of damage.
[Wed Aug 26 00:02:18 2015] A snake tries to hit YOU, but misses!
[Wed Aug 26 00:02:20 2015] You kick a snake for 1 point of damage.
[Wed Aug 26 00:02:21 2015] You try to punch a snake, but miss!
[Wed Aug 26 00:02:21 2015] A snake hits YOU for 4 points of damage.
[Wed Aug 26 00:02:24 2015] A snake tries to hit YOU, but misses!
[Wed Aug 26 00:02:25 2015] You try to punch a snake, but a snake parries!
[Wed Aug 26 00:02:27 2015] A snake tries to hit YOU, but misses!
[Wed Aug 26 00:02:28 2015] You kick a snake for 1 point of damage.
[Wed Aug 26 00:02:28 2015] You try to punch a snake, but miss!
[Wed Aug 26 00:02:30 2015] A snake hits YOU for 2 points of damage.
[Wed Aug 26 00:02:32 2015] You try to punch a snake, but miss!
[Wed Aug 26 00:02:33 2015] A snake tries to hit YOU, but misses!
[Wed Aug 26 00:02:36 2015] You punch a snake for 5 points of damage.
[Wed Aug 26 00:02:36 2015] A snake hits YOU for 1 point of damage.
[Wed Aug 26 00:02:37 2015] You kick a snake for 1 point of damage.
[Wed Aug 26 00:02:39 2015] A snake hits YOU for 1 point of damage.
[Wed Aug 26 00:02:40 2015] You gain experience!!
[Wed Aug 26 00:02:40 2015] You punch a snake for 6 points of damage.
[Wed Aug 26 00:02:40 2015] You have slain a snake!
[Wed Aug 26 00:02:42 2015] --You have looted a Snake Egg.--
[Wed Aug 26 00:02:42 2015] <SYSTEMWIDE_MESSAGE>: Innoruuk has been defeated by a group of hardy adventurers! Please join us in congratulating Harken along with everyone else who participated in this achievement!
[Wed Aug 26 00:02:43 2015] --You have decided to not loot 1 item(s): Snake Scales. The item(s) will be available to anyone after the corpse(s) unlock.--
[Wed Aug 26 00:02:46 2015] Auto attack is on.
[Wed Aug 26 00:02:46 2015] You punch a large rat for 6 points of damage.
[Wed Aug 26 00:02:46 2015] A large rat tries to bite YOU, but misses!
[Wed Aug 26 00:02:47 2015] You try to kick a large rat, but miss!
[Wed Aug 26 00:02:47 2015] You punch a large rat for 6 points of damage.
[Wed Aug 26 00:02:49 2015] A large rat bites YOU for 1 point of damage.
[Wed Aug 26 00:02:51 2015] You gain experience!!
[Wed Aug 26 00:02:51 2015] You punch a large rat for 5 points of damage.
[Wed Aug 26 00:02:51 2015] You have slain a large rat!
[Wed Aug 26 00:02:53 2015] --You have decided to not loot 1 item(s): Piece of Rat Fur. The item(s) will be available to anyone after the corpse(s) unlock.--
[Wed Aug 26 00:02:53 2015] --You have decided to not loot 2 item(s): Scalded Rat Skin. The item(s) will be available to anyone after the corpse(s) unlock.--
[Wed Aug 26 00:02:56 2015] Auto attack is on.
[Wed Aug 26 00:02:56 2015] You try to punch a large rat, but miss!
[Wed Aug 26 00:02:56 2015] A large rat bites YOU for 1 point of damage.
[Wed Aug 26 00:02:57 2015] You kick a large rat for 1 point of damage.

I have the log file path and name stored in the program's settings like so:

Properties.Settings.Default.setting_logfolder // Folder Path
Properties.Settings.Default.setting_logfile // File Name

I need to open the file when I click a button and read the file till the button is clicked again to stop the process, while the file is being read I need the lines that it finds to be output to a textbox for display to the user. The log file will still be written to by the parent program while this happens.

This is the code for the button that I have so far.

    private void btnStart_Click(object sender, EventArgs e)
    {
        if (btnStart.Text == "Start Parsing")
        {
            // change text on button and switch status image
            btnStart.Text = "Stop Parsing";
            pbStatus.Image = Properties.Resources.online;

            string logfile = Properties.Settings.Default.setting_logfolder += Properties.Settings.Default.setting_logfile;

            if (File.Exists(logfile))
            {
                Stream stream = File.Open(logfile, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
                StreamReader streamReader = new StreamReader(stream);
                string str = streamReader.ReadToEnd();
                tbOutput.AppendText(str);
                streamReader.Close();
                stream.Close();
            }
            else
            {
                tbOutput.AppendText(logfile);
            }
        }
        else
        {
            btnStart.Text = "Start Parsing";
            pbStatus.Image = Properties.Resources.offline;
        }
    }

I need it to keep reading the file until the button is pressed again and I only need lines like this one from the file

[Wed Aug 26 00:02:08 2015] <SYSTEMWIDE_MESSAGE>: XXXXXXXXX has been defeated by a group of hardy adventurers! Please join us in congratulating XXXXXX along with everyone else who participated in this achievement!

Solution

  • Here is a simple approach using FileWatcher Class

     public static Watchfile() 
     {
             FileSystemWatcher watch = new FileSystemWatcher();
             watch.Path = @"C:\";
             watch.Filter = "log.txt";
             watch.NotifyFilter = NotifyFilters.LastAccess |    
             NotifyFilters.LastWrite; 
    
            watch.Changed += new FileSystemEventHandler(OnChanged);
           watch.EnableRaisingEvents = true;
      }
    
    
     private static void OnChanged(object source, FileSystemEventArgs e)
     {
    
    
        string line;
             if (e.FullPath == @"C:\log.txt")
             {
                 Regex _regex = new Regex(@"\[[\w :]+\] <SYSTEMWIDE_MESSAGE>: \w+ has been defeated by a group of hardy adventurers! Please join us in congratulating \w+ along with everyone else who participated in this achievement!");
                 System.IO.StreamReader file =
                           new System.IO.StreamReader(@"C:\log.txt");
    
                 while ((line = file.ReadLine()) != null)
                 {
                     Match match = _regex.Match(line);
                     if (match.Success)
                     {
    
                         //Match Found
    
                     }
    
    
                 }
    
                 file.Close();
             }
    
    
     }