Dim d As Date = Date.Today
Dim bh As String = "MY" & Format(d,"yyyyMM") '生成编号的前6位,4位年,2位月.
If e.DataRow("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(编号)","编号 like '" & bh & "%' 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(8,4)) + 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("编号") = bh & Format(idx,"0000")
End If