public MResultModel ChangeClassRank(ChangeClassRankModel inputM) { MResultModel resM; try { _classListBLL.ChangeClassRank(inputM.ClassID, inputM.TargetClassID); resM = MResultModel.GetSuccessResultM("调换成功"); } catch (ArgumentNullException ex) { resM = MResultModel.GetFailResultM(ex.Message); } catch (ArgumentException ex) { resM = MResultModel.GetFailResultM(ex.Message); } return(resM); }