主题：通过代码自动生成订单号

Datacolchanged代码

Select e.DataCol.Name
    Case "订货客户"
        If e.DataRow.IsNull("订货客户") Then
            e.DataRow("订单号") = Nothing
        Else
            Dim fdr As DataRow = DataTables("客户").Find("名称 = '" & e.DataRow("订货客户") & "'")
            If fdr IsNot Nothing Then
                Dim lb As String = fdr("客户代码")
                If e.DataRow("订单号").StartsWith(lb) = False '如果单据编号前缀不符
                    Dim max As String
                    Dim idx As Integer
                    max = e.DataTable.Compute("Max(订单号)","订单号 like '" & lb & "*' And [_Identify] <> " & e.DataRow("_Identify")) '取得该类别的最大编号
                    If max > "" Then '如果存在最大编号
                        idx = CInt(max.Substring(lb.length,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
                    e.DataRow("订单号") = lb & Format(idx,"000")
                End If
            End If
           
        End If
End Select