Select e.DataCol.Name
Case "装箱日期","流向"
If e.DataRow.IsNull("装箱日期") OrElse e.DataRow.IsNull("流向") Then
e.DataRow("订单编号") = Nothing
Else
Dim d As Date = e.DataRow("装箱日期")
Dim y As Integer = d.Year
Dim m As Integer = d.Month
Dim Days As Integer = Date.DaysInMonth(y,m)
Dim fd As Date = New Date(y,m,1) \'获得该月的第一天
Dim ld As Date = New Date(y,m,Days) \'获得该月的最后一天
Dim bh As String = e.DataRow("流向") & "-" & Format(d,"yyyyMM") & "-" \'生成编号的前缀
If e.DataRow("订单编号").StartsWith(bh) = False \'如果订单编号前缀不符
Dim max As String
Dim idx As Integer
Dim flt As String
flt = "流向 = \'"& e.DataRow("流向") & "\' And 装箱日期 >= #" & fd & "# And 装箱日期 <= #" & ld & "# And [_Identify] <> " & e.DataRow("_Identify")
max = e.DataTable.Compute("Max(订单编号)",flt) \'取得该月的相同流向的最大订单编号
If max > "" Then \'如果存在最大订单编号
idx = CInt(max.Substring(12,4)) + 1 \'获得最大订单编号的后四位顺序号,并加1
Else
idx = 1 \'否则顺序号等于1
End If
e.DataRow("订单编号") = bh & Format(idx,"0000")
End If
End If
End Select