<EditItemTemplate>
    <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" >
        <asp:ListItem Value="采购">采购</asp:ListItem>
        <asp:ListItem Value="销售">销售</asp:ListItem>
    </asp:DropDownList>
</EditItemTemplate>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" 
                    ConnectionString="<%$ ConnectionStrings:ConnectionString %>" 
                    UpdateCommand="UPDATE [QuoTable] SET [xyz] = @xyz WHERE [id] = @id">
                        <UpdateParameters>
                        <asp:Parameter Name="xyz" Type="String" />
                        <asp:Parameter Name="id" Type="Int32" />
                    </UpdateParameters>如何将下拉列表的值赋给更新的参数啊?