请教高手

Private Sub Combo4_Click()
Set GxfpRs = New Recordset
If Option1(Index).Caption = "品种" Or Option1(Index).Caption = "加工工序" Then

   GxfpRs.Open "select * from 产品", con, adOpenDynamic, adLockOptimistic
         Combo4.Clear
   While Not (GxfpRs.EOF Or GxfpRs.BOF)
         Combo4.AddItem GxfpRs!产品名
         GxfpRs.MoveNext
   Wend
End If
GxfpRs.Close
End Sub
为什么这段代码不起做用呢？他也不报错