组合框随设置变换列表项？

[feng_1974]

我想实现如下功能：
两个组合框，一个显示类别，一个显示商品名称，当选择第一个框的类别后，第二个组合框能显示出属于该类别的所有商品名称，请问应该怎么实现？谢谢！

[SYSSZ]

Private Declare Function SendMessageLong Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Private Const CB_SHOWDROPDOWN = &H14F

Private Sub Combo1_Click()
If Combo1.Text = "电器" Then
Combo2.Clear
Combo2.AddItem "电视"
Combo2.AddItem "电冰箱"
Combo2.AddItem "空调"
r = SendMessageLong(Combo2.hwnd, CB_SHOWDROPDOWN, True, 0)

End If
If Combo1.Text = "纺织品" Then
Combo2.Clear
Combo2.AddItem "毛巾"
Combo2.AddItem "床单"
Combo2.AddItem "被子"
r = SendMessageLong(Combo2.hwnd, CB_SHOWDROPDOWN, True, 0)

End If
If Combo1.Text = "日用品" Then
Combo2.Clear
Combo2.AddItem "肥皂"
Combo2.AddItem "洗发精"
Combo2.AddItem "饭碗"
r = SendMessageLong(Combo2.hwnd, CB_SHOWDROPDOWN, True, 0)

End If

End Sub

[feng_1974]

谢谢！

[SYSSZ]

从我的测试程序上拷过来时还丢几句:

Private Sub Form_Load()
Combo1.AddItem "电器"
Combo1.AddItem "纺织品"
Combo1.AddItem "日用品"
End Sub