'你反向操作不就行了么
Select Case e.DataCol.Name Case "预计日期","天数" If e.DataRow.IsNull("预计日期") OrElse e.DataRow.IsNull("天数") Then e.DataRow("还货日期") = Nothing Else Dim dt As Date = e.DataRow("预计日期") e.DataRow("还货日期") = dt.AddDays(e.DataRow("天数")) End IfEnd Select