主题：自动编号

项目放在服务器上，按照下面的编号方法，现在会出现重号，要怎么改？

If e.DataCol.Name = "编制日期" Then
    If e.DataRow.IsNull("编制日期") Then
        e.DataRow("预算编号") = Nothing
    Else
        Dim d As Date = e.DataRow("编制日期")
        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 = Format(d,"yyyyMM") '生成编号的前6位,4位年,2位月.
        If e.DataRow("预算编号").StartsWith(bh) = False '如果编号的前6位不符
            Dim max As String
            Dim idx As Integer
            max = e.DataTable.Compute("Max(预算编号)","编制日期 >= #" & fd & "# And 编制日期 <= #" & ld & "# And [_Identify] <> " & e.DataRow("_Identify")) '取得该月的最大编号
            If max > "" Then '如果存在最大编号
                idx = CInt(max.Substring(13,3)) + 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("预算编号") ="WZ-FJ-" & bh & "-" & Format(idx,"000")
            e.DataRow.Save
        End If
    End If
End If

参考

http://www.foxtable.com/bbs/dispbbs.asp?BoardID=2&ID=128569&skin=0

If e.DataCol.Name = "编制日期" Then
    If e.DataRow.IsNull("编制日期") Then
        e.DataRow("预算编号") = Nothing
    Else
        Dim d As Date = e.DataRow("编制日期")
        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 = Format(d,"yyyyMM") '生成编号的前6位,4位年,2位月.
        If e.DataRow("预算编号").StartsWith(bh) = False '如果编号的前6位不符
            Dim max As String
            Dim idx As Integer
            max = e.DataTable.sqlCompute("Max(预算编号)","编制日期 >= #" & fd & "# And 编制日期 <= #" & ld & "# And [_Identify] <> " & e.DataRow("_Identify")) '取得该月的最大编号
            msgbox(max)
            If max > "" Then '如果存在最大编号
                idx = CInt(max.Substring(13,3)) + 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("预算编号") ="WZ-FJ-" & bh & "-" & Format(idx,"000")
            e.DataRow.Save
        End If
    End If
End If

放在datarowadding里？

我是放在datacolchanged！

执行下面的代码，看能否得到正常结果。

If e.DataCol.Name = "编制日期" Then
    If e.DataRow.IsNull("编制日期") Then
        e.DataRow("预算编号") = Nothing
    Else
        Dim d As Date = e.DataRow("编制日期")
        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 = Format(d,"yyyyMM") '生成编号的前6位,4位年,2位月.
        If e.DataRow("预算编号").StartsWith(bh) = False '如果编号的前6位不符
            Dim max As String
            Dim idx As Integer
            max = e.DataTable.sqlCompute("Max(预算编号)","编制日期 >= '" & fd & "' And 编制日期 <= '" & ld & "' And [_Identify] <> " & e.DataRow("_Identify")) '取得该月的最大编号
            msgbox(max)
            If max > "" Then '如果存在最大编号
                idx = CInt(max.Substring(13,3)) + 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("预算编号") ="WZ-FJ-" & bh & "-" & Format(idx,"000")
            e.DataRow.Save
        End If
    End If
End If

access数据库，改成

max = e.DataTable.sqlCompute("Max(预算编号)","编制日期 >= #" & fd & "# And 编制日期 <= #" & ld & "# And [_Identify] <> " & e.DataRow("_Identify")) '取得该月的最大编号

Dim dr As DataRow = e.DataRow
Select Case e.DataCol.Name
    Case "生产令号"
        If dr.IsNull("生产令号") Then
            dr("制单日期") = Nothing
        Else
            dr("制单日期") = Date.today
        End If
End Select

If e.DataCol.Name = "制单日期" Then
    If e.DataRow.IsNull("制单日期") Then
        e.DataRow("零部件编号") = Nothing
    Else
        Dim d As Date = e.DataRow("制单日期")
        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 = Format(d,"yyyyMM") '生成编号的前6位,4位年,2位月.
        If e.DataRow("零部件编号").StartsWith(bh) = False '如果编号的前6位不符
            Dim max As String
            Dim idx As Integer
            max = e.DataTable.sqlCompute("Max(零部件编号)","制单日期 >= #" & fd & "# And 制单日期 <= #" & ld & "# And [_Identify] <> " & e.DataRow("_Identify")) '取得该月的最大编号
                    If max > "" Then '如果存在最大编号
                idx = CInt(max.Substring(9,4)) + 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("零部件编号") = "JG" & bh & "-" & Format(idx,"0000")
            e.DataRow.Save
        End If
    End If
End If

现在的问题：生成零部件编号以后

若“生产令号”变化，“制单日期”会更新至最新日期，导致“零部件编号”随之变化，

如何更改，在生成零部件编号后，更改“生产令号”，“制单日期”不会变化？

判断【零部件编号】是否为空，为空的情况下，才生成

If e.DataCol.Name = "制单日期" andalso e.DataRow("零部件编号") <> nothing Then