On update the dropdown value shows NULL in database : here's structure for my gridview
<asp:TemplateField HeaderText="Construction Phase" SortExpression="Phase_Name">
<EditItemTemplate>
<asp:DropDownList ID="EditedDropDownInGrid" runat="server" CssClass="form-control" DataSourceID="PhaseSQLDataSource" DataTextField="pp_name" DataValueField="pp_id">
</asp:DropDownList>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label3" runat="server" Text='<%# Bind("Phase_Name") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:SqlDataSource ID="ExistingSqlSource" runat="server" ConnectionString="<%$ ConnectionStrings:BSDConnectionString %>"
deletecommand="UPDATE [dbo].[d_activity] SET [act_dell] = 1, [act_dell_date] = GETDATE(), [act_deletedBy_Prefix] = @DelPrefix WHERE [act_id] = @act_id"
UpdateCommand ="UPDATE [dbo].[d_activity] SET act_pp_id = @Phase_Name , act_name = @Act_Name , act_lastupdateby = @lastUpdateBy , act_lastupdatedate = GetDate(), act_lastUpdateBy_Prefix = @lastUpdatePrefix WHERE act_id = @act_id"
>
<deleteparameters>
<asp:SessionParameter Name="DelPrefix" SessionField="Prefix" />
<asp:parameter name="act_id" type="Int32" />
</deleteparameters>
<UpdateParameters>
<asp:SessionParameter Name="lastUpdateBy" SessionField="LogInID" />
<asp:SessionParameter SessionField="Prefix" Name="lastUpdatePrefix" />
<asp:Parameter Name="Phase_Name" type="Int32"/>
<asp:Parameter Name="Act_Name" Type="String" />
<asp:parameter name="act_id" type="Int32" />
</UpdateParameters>
</asp:SqlDataSource>
it updates other controls in gridview but does not update my selected dropdowns item value in Integer format which is inside gridview