主题：窗口的组合框可以设置多值字段吗

 不可以，你用下拉窗口吧。

http://www.foxtable.com/help/topics/2466.htm

Dim nms1() As String = e.Form.Controls("品牌T1").text.Split(",")
Dim nms2() As String = e.Form.Controls("品牌T2").text.Split(",")
Dim filter1 As String = ""
Dim filter2 As String = ""
If e.Form.Controls("品牌T1").text > "" Then
    filter1 = "品牌 = '" & nms1(0) & "'"
    For  i As Integer = 1 To nms1.Length-1
        filter1=filter1 & " or 品牌 = '" & nms1(i) & "'"
    Next
End If
If e.Form.Controls("品牌T2").text > "" Then
    filter2 = "品牌 = '" & nms2(0) & "'"
    For  i As Integer = 1 To nms2.Length-1
        filter2=filter2 & " or 品牌 = '" & nms2(i) & "'"
    Next
End If

Tables("数据看板_Table3").DataSource = sg.BuildDataSource()
Tables("数据看板_Table3").Filter = Filter2
Tables("数据看板_Table2").DataSource = sg.BuildDataSource()
Tables("数据看板_Table2").Filter = filter1