我有一个带有取消按钮的DialogBox，调用如下:DimdlgSizSelectionAsNewdlgTyreSizeSelection(objCarWebVehicle.Tyres,objCarWebVehicle)If(dlgSizSelection.ShowDialog)=Windows.Forms.DialogResult.OKThenselectedTyre=CType(dlgSizSelection.lstTyreOptions.SelectedItem,CarWebVehicleCOM.TyreData)dlgSizSelection.Close()ElseIf(dlg