((System.Exception)((new System.Linq.SystemCore_EnumerableDebugView<Schedulazioni>
(_dataContext.Schedulazionis)).Items)).StackTrace
at System.Data.Linq.DBConvert.ChangeType(Object value, Type type)
   at Read_Schedulazioni(ObjectMaterializer`1 )
   at System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReader`2.MoveNext()
   at System.Linq.SystemCore_EnumerableDebugView`1.get_Items()
Data at the root level is invalid. Line 1, position 1.

dbo.GetSchedulationByNextDate
AS
  Select * from dbo.Schedulazioni
  order by NextDate asc
  RETURN

[Function(Name="dbo.GetSchedulationByNextDate")]
  public ISingleResult<Schedulazioni> GetSchedulationByNextDate()
  {
    IExecuteResult result = this.ExecuteMethodCall(this, ((MethodInfo)(MethodInfo.GetCurrentMethod())));
    return ((ISingleResult<Schedulazioni>)(result.ReturnValue));
  }

System.Data.Linq.ISingleResult<Schedulazioni> next = _dataContext.GetSchedulationByNextDate().ReturnValue;

_dataContext = new DataClassesDataContext();
        ;
        Nullable<int> pp = new int();
        // Controlliamo il numero di schedulazioni in tabella
        _dataContext.NumberOfSchedulation(ref pp);