[2.0] Efficiency check!

Objective:

Get the last line or 2 of a log file that's anywhere between 1kb and 600kb on average.

The initial parse function:

Code:

---

        public void ParseLogFile(string fullLogPath)
        {
            string[] logLines = File.ReadAllLines(fullLogPath, Encoding.UTF7);

            int lastLineIndex = logLines.GetUpperBound(0);

            if (logLines[lastLineIndex - 1].IndexOf("±â") > 0) ParseHeader(logLines[lastLineIndex - 1].Substring(logLines[lastLineIndex - 1].LastIndexOf(": ") + 2));
            if (logLines[lastLineIndex].IndexOf("¹ø") > 0) ParseBody(logLines[lastLineIndex].Substring(logLines[lastLineIndex].LastIndexOf(": ") + 2));
            if (logLines[lastLineIndex].IndexOf("ÅÏ :") > 0) ParseFooter(logLines[lastLineIndex].Substring(logLines[lastLineIndex].LastIndexOf(": ") + 2));
        }

---

Seperate functions that handle parsing a specific line:

Code:

---

        private void ParseHeader(string logLine)
        { 
            string[] headerInfoArray;
            string startAtSection = string.Empty;
            string[] splitter = { " " };

            startAtSection = logLine.Substring(logLine.LastIndexOf(":") + 1);

            headerInfoArray = startAtSection.Split(splitter, StringSplitOptions.None);

            Header.Title = headerInfoArray[0];
            Header.Tags = headerInfoArray[1];
        }

---

The others are similiar to the one posted above. Don't need to post it.

ParseLogFile() gets called everytime the filesystemwatcher event triggers, which is usually every 5-15 seconds.

Is there any way I could make this better?

Edit:

Might as well throw this question in here too rather than make a new post. At the moment in that filesystemwatcher event I am using Thread.Sleep(200) before I parse the file because without it I kept randomly getting a "file is in use by another process, you can't read this file" error.

Also without the sleep thrown in there the log file was actually getting corrupted occasionally. Once in a while it would skip a few lines that should have been logged.

Is there a more proper way of telling my program to wait until the file has been closed by the log owner's app before I read it?