如何在gridview表头添加dropdownlist以便查询?

<head runat="server">
    <title>无标题页</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:AccessDataSource ID="AccessDataSource1" runat="server" DataFile="~/xtreme.mdb"
            SelectCommand="SELECT [产品名称], [产品 ID] AS 产品_ID FROM [产品]"></asp:AccessDataSource>
        <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" DataSourceID="AccessDataSource1"
            DataTextField="产品名称" DataValueField="产品_ID">
        </asp:DropDownList>
        &nbsp;
        <asp:AccessDataSource ID="AccessDataSource2" runat="server" DataFile="~/xtreme.mdb"
            SelectCommand="SELECT * FROM [产品] WHERE ([产品 ID] = ?)">
            <SelectParameters>
                <asp:ControlParameter ControlID="DropDownList1" Name="产品_ID" PropertyName="SelectedValue"
                    Type="Int32" />
            </SelectParameters>
        </asp:AccessDataSource>
        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="产品_ID"
            DataSourceID="AccessDataSource1">
            <Columns>
                <asp:BoundField DataField="产品名称" HeaderText="产品名称" SortExpression="产品名称" />
                <asp:BoundField DataField="产品_ID" HeaderText="产品_ID" ReadOnly="True" SortExpression="产品_ID" />
            </Columns>
        </asp:GridView>
    </div>
    </form>
</body>
</html>