I have a details view where I have a date textbox and a time textbox. I am using a dataset to insert and update to the database. I need to combine the date and time textboxes to a single parameter to be entered into the database to a datetime field. My detailsview and dataobject are below. Help is appreciated.

Code:
<asp:DetailsView ID="DetailsView1" runat="server" AutoGenerateRows="False" DataKeyNames="training_id"
        DataSourceID="ObjectDataSource1" Height="50px" Width="125px">
        <Fields>
            <asp:TemplateField HeaderText="Type">
                <EditItemTemplate>
                    <asp:DropDownList ID="DropDownList1" runat="server" DataSourceID="SqlDataSource1"
                        DataTextField="session_type_name" DataValueField="session_type_name" AppendDataBoundItems="True" SelectedValue='<%# Bind("training_type") %>'>
                        <asp:ListItem Selected="True" Value="NULL">Select Training Type</asp:ListItem>
                    </asp:DropDownList><asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:UserConferenceConnectionString %>"
                        SelectCommand="SELECT [session_type_name] FROM [training_session_type]"></asp:SqlDataSource>
                </EditItemTemplate>
                <ItemTemplate>
                    <asp:Label ID="Label1" runat="server" Text='<%# Eval("training_type") %>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Start Date">
                <EditItemTemplate>
                    <asp:TextBox ID="start_date" runat="server"></asp:TextBox>
                </EditItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Start Time">
                <EditItemTemplate>
                    <asp:TextBox ID="start_time" runat="server"></asp:TextBox>
                </EditItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="End Date">
                <EditItemTemplate>
                    <asp:TextBox ID="end_date" runat="server"></asp:TextBox>
                </EditItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="End Time">
                <EditItemTemplate>
                    <asp:TextBox ID="end_time" runat="server"></asp:TextBox>
                </EditItemTemplate>
            </asp:TemplateField>
            <asp:BoundField DataField="training_title" HeaderText="Title" SortExpression="training_title" />
            <asp:BoundField DataField="reg_link" HeaderText="Registration" SortExpression="reg_link" />
            <asp:BoundField DataField="training_loc" HeaderText="Location" SortExpression="training_loc" />
            <asp:BoundField DataField="detail_link" HeaderText="More Details Link" SortExpression="detail_link" />
            <asp:CommandField ShowDeleteButton="True" ShowEditButton="True" />
        </Fields>
    </asp:DetailsView>
    &nbsp;&nbsp;
    <asp:ObjectDataSource ID="ObjectDataSource1" runat="server" DeleteMethod="Delete"
        InsertMethod="Insert" OldValuesParameterFormatString="original_{0}" SelectMethod="GetDataByTrainingID"
        TypeName="TrainingEventsTableAdapters.trainingTableAdapter" UpdateMethod="UpdateQuery">
        <DeleteParameters>
            <asp:Parameter Name="Original_training_id" Type="Int32" />
        </DeleteParameters>
        <UpdateParameters>
            <asp:Parameter Name="product_family" Type="String" />
            <asp:Parameter Name="training_type" Type="String" />
            <asp:Parameter Name="start_date" Type="String" />
            <asp:Parameter Name="start_time" Type="String" />
            <asp:Parameter Name="end_date" Type="String" />
            <asp:Parameter Name="end_time" Type="String" />
            <asp:Parameter Name="training_title" Type="String" />
            <asp:Parameter Name="reg_link" Type="String" />
            <asp:Parameter Name="training_loc" Type="String" />
            <asp:Parameter Name="detail_link" Type="String" />
            <asp:Parameter Name="page_id" Type="Int32" />
            <asp:Parameter Name="training_global_flag" Type="Int32" />
            <asp:Parameter Name="date_added" Type="DateTime" />
            <asp:Parameter Name="Original_training_id" Type="Int32" />
        </UpdateParameters>
        <SelectParameters>
            <asp:QueryStringParameter Name="training_id" QueryStringField="training_id" Type="Int32" />
        </SelectParameters>
        <InsertParameters>
            <asp:Parameter Name="product_family" Type="String" />
            <asp:Parameter Name="training_type" Type="String" />
            <asp:Parameter Name="training_start_date" Type="DateTime" />
            <asp:Parameter Name="training_end_date" Type="DateTime" />
            <asp:Parameter Name="training_title" Type="String" />
            <asp:Parameter Name="reg_link" Type="String" />
            <asp:Parameter Name="training_loc" Type="String" />
            <asp:Parameter Name="detail_link" Type="String" />
            <asp:Parameter Name="page_id" Type="Int32" />
            <asp:Parameter Name="training_global_flag" Type="Int32" />
            <asp:Parameter Name="date_added" Type="DateTime" />
        </InsertParameters>
    </asp:ObjectDataSource>