主题：网络的复杂编号

 If key = 4 Then key = 5

 

If key mod 10 = 4 Then key += 1

 取出每一位，看是不是4，如果是，对应的位置就+1

 你直接看最后生成的编号是否正确啊。

Dim dr As DataRow = e.DataRow
Dim pf As String
If dr.RowState <> DataRowState.Added Then '如果不是新增行
    Return '那么返回
ElseIf dr.IsNull("日期") Then '如果没有输入日期
    e.Cancel = True '取消保存此行
    MessageBox.Show("必须输入日期!","提示",MessageBoxButtons.OK,MessageBoxIcon.Information)
    Return
Else
    pf = Format(dr("日期"),"yyMM") '否则获得编号的前缀,两位年,两位月
End If
Dim cmd1 As New SQLCommand
Dim cmd2 As New SQLCommand
Dim Key As Integer
cmd1.C '设置数据源名称
cmd2.C
cmd1.commandText = "Select Count(*) From [编号] Where [前缀] = '" & pf & "'"
If cmd1.ExecuteScalar = 0 Then '如果编号表不存在前缀的行,那么增加一行
    cmd1.commandtext = "Insert Into 编号 (前缀, 顺序号) Values('" & pf & "',1)"
    cmd1.ExecuteNonQuery
End If
cmd1.commandText = "Select [顺序号] From [编号] Where [前缀] = '" & pf & "'"

Key = cmd1.ExecuteScalar() '从后台获得顺序号
Dim temp As String = key
For i As Integer = temp.Length - 1 To 0 Step -1
    If temp(i) = "4" Then
        temp = key + (temp.Length-1-i) * 10 + 1
        Exit For
    End If
Next
Do
    cmd2.commandText = "Update [编号] Set [顺序号] = " & (cint(temp)+1) & " Where [顺序号] = " & Key & " And [前缀] = '" & pf & "'"
    If cmd2.ExecuteNonQuery() > 0 Then '更新顺序号
        Exit Do '更新成功则退出循环
    End If
Loop

e.DataRow("编号") = pf & "-" & Format(cint(temp),"0000")

 测试没有问题，请认真测试