title: write text in new line(loop)
body: <p>i want to create a simple log file for and adding frames.<br>
  here is what i found so far.>br>
  this class invoked from another class which is executed in looping, so everytime the loop end it will call this calss and this class will write a log(data created in time). But, all i got is everytime a new string written in txt file it only replace the first one.
  how can i add a new string in new line without replacing the old one?<br>
  i read the <code>environment.newline</code> but i dont get it.</p>
  
  <pre><code>    private void logFile()
      {
          StreamWriter logfile = null;
          logfile = File.CreateText(Server.MapPath("/CCTV_Files/log.txt"));
          try
          {
              logfile.Write(String.Format("{0:yyyyMMdd_hhmmss}", DateTime.Now) + " Frame added");
          }
          catch (IOException e)
          {
              Console.WriteLine(e);
          }
          catch (Exception e)
          {
              Console.WriteLine(e);
          }
          finally
          {
              if (logfile != null)
              {
                  logfile.Close();
              }
          }
       }
  </code></pre>