EXCEL VBA 自動流水號

Sub 流水號()
Dim mystart, myend, myrow, myrow1

myrow = ActiveCell.Row

ActiveCell.Offset(0, 1).Select

myrow1 = Selection.End(xlDown).Row

myend = myrow1 - myrow + 1

ActiveCell.Offset(0, -1).Select

mystart = ActiveCell.Value



If mystart <> Empty Then

ActiveCell.Value = mystart

myend = myend - 1


Else

ActiveCell.Value = 1

mystart = 0


End If


Selection.DataSeries Rowcol:=xlColumns, Type:=xlLinear, Date:=xlDay, _

Step:=1, Stop:=myend + mystart, Trend:=False

End Sub