TraceListener vs Try-Catch?

Q. What's the difference between using TraceListeners and placeing a Try-Catch on every method???

Q. Looks like I would need a Try-Catch anyway in order to use the Trace.WriteLine method???

I've been using the following code on every method to catch errors. It calls a class implementing a StreamWriter to write both method() name and exception message to a c:\log.txt......  The log.tx is also encrypted to keep prying eyes from reading the detailed exceptions (ie... methods, line numbers, etc...) Encryption can also be disabled for my eyes only or I can decrypt a log sent to me from a client.

Try
{
      //code....
}
catch (Exception ex)
{      
      EventLogWriter.Write(" Form1_Load() " + ex.ToString(), "Error");
}