第二行就错了

报错说 \'DataCol\' is not a member of \'DataTable\'

应该改哪里？怎么改啊？

Dim cp As DataTable = DataTables("产品表")

If cp.DataCol.Name = "订单编号" Then

    If cp.DataRow.IsNull("选择") Then

        cp.DataRow("订单编号") = Nothing

    Else

        Dim d As Date = Date.Today

        Dim y As Integer = d.Year

        \'Dim m As Integer = d.year

        \'Dim Days As Integer = Date.DaysInMonth(y,m)

        Dim fd As Date = New Date(y,1,1) \'获得该月的第一天

        Dim ld As Date = New Date(y,12,31) \'获得该月的最后一天

        Dim bh As String = Format(d,"yyyy") \'生成编号的前6位,4位年,2位月.

        If cp.DataRow("订单编号").StartsWith(bh) = False \'如果编号的前6位不符

            Dim max As String

            Dim idx As Integer

            max = cp.DataTable.Compute("Max(订单编号)","日期 >= #" & fd & "# And 日期 <= #" & ld & "#")   \'取得该月的最大编号

            If max > "" Then \'如果存在最大编号

                idx = CInt(max.Substring(5,3)) + 1 \'获得最大编号的后三位顺序号,并加1

            Else

                idx = 1 \'否则顺序号等于1

            End If

            cp.DataRow("订单编号") = bh & "-" & Format(idx,"000")

        End If

    End If

End If