Question

at the moment i am using a while (true) loop to do this. I am not very familiar with timers. can someone tell me how i would convert this to work with a timer?

string lyricspath = @"c:\lyrics.txt";
TextReader reader = new StreamReader(lyricspath);
int start = 0;
string[] read = File.ReadAllLines(lyricspath);
string join = String.Join(" ", read);
int number = join.Length;
while (true)
{
    Application.DoEvents();
    Thread.Sleep(200);
    start++;
    string str = join.Substring(start, 15);
    byte[] bytes = Encoding.BigEndianUnicode.GetBytes(str);
    label9.Text = str;
    if (start == number - 15)
    {
        start = 0;
    }
}

Answer 1

Why use a timer? I assume this is because you want to have the app remain responsive during such a supposedly long operation. If so cosider using the same sort of code but in a BackgroundWorker.

Also if you do specifically want to use a Timer, beware which one you use; the Systm.Timer invokes its event in a different thread to the one used by the applications hoting form. The Timer in Forms events in the forms thread. You may need to Invoke() the operations in a timer callback that change the label.