Logging Exceptions/Errors in log file

using System.IO;
      
public string GetTempPath()
{
   string path = System.Environment.GetEnvironmentVariable("TEMP");
   if (!path.EndsWith("\\")) path += "\\";
   return path;
}

public void LogMessageToFile(string msg)
{
   System.IO.StreamWriter sw = System.IO.File.AppendText(
       GetTempPath() + "My Log File.txt");
   try
   {
       string logLine = System.String.Format(
           "{0:G}: {1}.", System.DateTime.Now, msg);
       sw.WriteLine(logLine);
   }
   finally
   {
       sw.Close();
   }
}

With this simple method, all you need to do is to pass in a string like this:

LogMessageToFile("Hello, World");

The current date and time are automatically inserted to the log file along with your message.