public static string Lookup(DataSource dataSourceName, object id)
 {
     object val = dataSourceName.Lookup(null, id, null, null);
     if (val == null)
     {
         val = "";
     }
     return BaseFormulaUtils.Format(val, "");
 }
 public static object Lookup(DataSource dataSourceName, object rowNumber, object id, object idColumn, object valueColumn)
 {
     return dataSourceName.Lookup(rowNumber, id, idColumn, valueColumn);
 }