主题：click 代码 帮忙看看

Dim a0 As WinForm.DropDownBox = e.Form.Controls("DropDownBox1")

If a0.value IsNot Nothing Then

    messagebox.show("请先输入商品名称!")

    e.Cancel = True

     Else

    e.Cancel = True

    Forms("入库选择").Open()

End If