<asp:DropDownList ID="sq" runat="server"  
            DataSourceID="AccessDataSource1" DataTextField="nome" DataValueField="nome" Visible="false" Font-Size="11px">
        </asp:DropDownList>
        <asp:AccessDataSource ID="AccessDataSource1" runat="server" 
            DataFile="~/App_data/DB.mdb" 
            
            SelectCommand="SELECT [ID], [nome] FROM [squadre] WHERE ([stagione] = ?) ORDER BY [nome]">
            <SelectParameters>
                <asp:Parameter DefaultValue="8" Name="stagione" Type="Int32" />
            </SelectParameters>
        </asp:AccessDataSource>

string sq1 = this.sq.SelectedValue;

//quello che mi servirebbe

int sq1 = ????;