试试
Dim cr = Tables("生产在制品").current
Dim d As Date = cr("下达日期")
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 max As String
Dim idx As Integer
max = Tables("毛坯工序维护_条码维护").DataTable.sqlCompute("Max(毛坯编码)","下达日期 >= #" & fd & "# And 下达日期 <= #" & ld & "#") '取得该月的最大编号
If max > "" Then '如果存在最大编号
idx = CInt(max.Substring(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
For i As Integer = 1 To cr("计划数量")
Dim r As Row = Tables("毛坯工序维护_条码维护").addnew
r("成品编码") = cr("成品编码")
r("成品描述") = cr("成品描述")
r("毛坯产地") = cr("毛坯产地")
r("生产批次") = cr("生产批次")
r("投产日期") = cr("下达日期")
r("毛坯编码") = format(cr("下达日期"), "yyMM") & format(i+idx-1, "0000")
r("批次序号") =format(i, "0")
Next