C#

TextWriterTraceListener myTrace = new TextWriterTraceListener(File.CreateText(@"c:\Output.txt"));
Debug.Listeners.Add(myTrace);

public DataTable Request()<br />
{<br />
  try<br />
  {<br />
    using (OleDbConnection connection = new OleDbConnection(Constants.DB2_CONNECTION_STRING))<br />
    {<br />
      using (OleDbDataAdapter da = new OleDbDataAdapter(request, connection))<br />
      {<br />
        using (DataTable dtResult = new DataTable())<br />
        {<br />
          da.Fill(dtResult);<br />
          return dtResult;<br />
        }<br />
      }<br />
    }<br />
  }<br />
  catch (Exception ex)<br />
  {<br />
    MessageBox.Show(ex.ToString());<br />
  }<br />
  return null;<br />
}<br />

static void Main()
       {
          ServiceBase[] ServicesToRun;
         // More than one user Service may run within the same process. To add
        // another service to this process, change the following line to
       // create a second service object. For example,
       //   ServicesToRun = new ServiceBase[] {new Service1(), new MySecondUserService()};
           //

           ServicesToRun = new ServiceBase[] { new Service1() };
           ServiceBase.Run(ServicesToRun);
       }