If e.DataCol.Name ="订单退单" Then
或者
Dim dr1 As DataRow = e.DataRowSelect Case e.DataCol.Name Case "订单金额","预付订金","未付余款" dr1("未付余款") = dr1("订单金额")-dr1("预付订金") Case "订单退单" Dim dr2 As DataRow = DataTables("表A").Find("未付余款 '" & e.OldValue & "'") dr2("未付余款") = NothingEnd Select