Classe per la scrittura nei log di SharePoint 2010

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.SharePoint.Administration;

namespace Sgart
{
  public class LoggingService : SPDiagnosticsService
  {
    public const string INFO = "Sgart Info";
    public const string WARNING = "Sgart Warning";
    public const string ERROR = "Sgart Error";
    public const string PRODUCTNAME = "Sgart sample";

    public LoggingService()
      : base("Sgart.it", SPFarm.Local)
    {
    }

    protected override IEnumerable<SPDiagnosticsArea> ProvideAreas()
    {
      List<SPDiagnosticsArea> areas = new List<SPDiagnosticsArea>{
        new SPDiagnosticsArea(PRODUCTNAME, new List<SPDiagnosticsCategory>{
          new SPDiagnosticsCategory(INFO, TraceSeverity.Verbose, EventSeverity.Information)
          , new SPDiagnosticsCategory(WARNING, TraceSeverity.Monitorable, EventSeverity.Information)
          , new SPDiagnosticsCategory(ERROR, TraceSeverity.Unexpected, EventSeverity.ErrorCritical)
        })
      };

      return areas;
    }

    private static LoggingService _current;
    public static LoggingService Current
    {
      get
      {
        if (_current == null)
          _current = new LoggingService();
        return _current;
      }
    }

    public static void WriteInfo(string message)
    {
      SPDiagnosticsCategory category = Current.Areas[PRODUCTNAME].Categories[INFO];
      Current.WriteTrace(0, category, TraceSeverity.Verbose, message);
    }

    public static void WriteWarning(string message)
    {
      SPDiagnosticsCategory category = Current.Areas[PRODUCTNAME].Categories[WARNING];
      Current.WriteTrace(0, category, TraceSeverity.Medium, message);
    }

    public static void WriteWarning(Exception ex)
    {
      WriteError(ex.ToString());
    }
    public static void WriteError(string message)
    {
      SPDiagnosticsCategory category = Current.Areas[PRODUCTNAME].Categories[ERROR];
      Current.WriteTrace(0, category, TraceSeverity.Unexpected, message);
    }
  }
}

LoggingService.WriteInfo("messaggio");
LoggingService.WriteWarning("messaggio");
LoggingService.WriteError("messaggio");
LoggingService.WriteError(exception);