/// <summary> /// select count(column) /// </summary> /// <param name="func">格式: it => it.Id</param> public SingleFilter <M> Count <F>(Expression <Func <M, F> > func) { var field = DC.EH.ExpressionHandle(func); DC.AddConditions(new DicModel { ColumnOne = field, Param = field, ParamRaw = field, Action = ActionEnum.Select, Option = OptionEnum.Count, Crud = CrudTypeEnum.Query }); return(new SingleFilter <M>(DC)); }