static Datums()
 {
     datumList = new List<Datum>();
     while (datumString.Contains(";")) {
         Datum d = new Datum();
         d.Name = datumString.Substring(0, datumString.IndexOf(","));
         datumString = datumString.Remove(0, datumString.IndexOf(",") + 1);
         d.EquatorialRadius = double.Parse(datumString.Substring(0, datumString.IndexOf(",")));
         datumString = datumString.Remove(0, datumString.IndexOf(",") + 1);
         d.PolarRadius = double.Parse(datumString.Substring(0, datumString.IndexOf(",")));
         datumString = datumString.Remove(0, datumString.IndexOf(",") + 1);
         d.Flattening = (d.EquatorialRadius - d.PolarRadius) / d.EquatorialRadius;
         datumString = datumString.Remove(0, datumString.IndexOf(",") + 1);
         d.Use = datumString.Substring(0, datumString.IndexOf(";"));
         datumString = datumString.Remove(0, datumString.IndexOf(";") + 1);
         datumList.Add(d);
     }
 }
 /// <summary>
 /// constructor for convert lat lon utm
 /// </summary>
 public ConvertLatLonUtm()
 {
     _datum = new Datum();
 }