<dx:ASPxGridView ID="ASPxGridView1" runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource1" EnableTheming="True" KeyFieldName="transaction_id" OnRowCommand="ASPxGridView1_RowCommand" OnRowUpdated="ASPxGridView1_RowUpdated" OnRowUpdating="ASPxGridView1_RowUpdating" Theme="Metropolis">
                    <Columns>
                        <dx:GridViewCommandColumn ShowDeleteButton="True" ShowEditButton="True" VisibleIndex="0">
                        </dx:GridViewCommandColumn>
                        <dx:GridViewDataTextColumn FieldName="item_number" VisibleIndex="1">
                        </dx:GridViewDataTextColumn>
                        <dx:GridViewDataTextColumn FieldName="item_description" VisibleIndex="2">
                        </dx:GridViewDataTextColumn>
                        <dx:GridViewDataTextColumn FieldName="item_unit" VisibleIndex="3">
                        </dx:GridViewDataTextColumn>
                        <dx:GridViewDataTextColumn FieldName="item_quantity" VisibleIndex="4">
                        </dx:GridViewDataTextColumn>
                        <dx:GridViewDataTextColumn FieldName="item_price" VisibleIndex="5">
                        </dx:GridViewDataTextColumn>
                        <dx:GridViewDataTextColumn FieldName="item_amount" VisibleIndex="6">
                        </dx:GridViewDataTextColumn>
                        <dx:GridViewDataTextColumn FieldName="voucher_number" VisibleIndex="7">
                        </dx:GridViewDataTextColumn>
                    </Columns>
                    <SettingsBehavior ConfirmDelete="True" />
                    <SettingsEditing Mode="PopupEditForm">
                    </SettingsEditing>
                    <Settings ShowFilterRow="True" ShowFooter="True" />
                </dx:ASPxGridView>
            </ContentTemplate>
        </asp:UpdatePanel>

        <br />

        <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:item_detailConnectionString %>" DeleteCommand="DELETE FROM [tbl_item_detail_transactions] WHERE [transaction_id] = @transaction_id" InsertCommand="INSERT INTO [tbl_item_detail_transactions] ([item_number], [item_description], [item_unit], [item_quantity], [item_price], [item_amount], [voucher_number]) VALUES (@item_number, @item_description, @item_unit, @item_quantity, @item_price, @item_amount, @voucher_number)" SelectCommand="SELECT  *, (item_quantity * item_price) as item_amount2 FROM [tbl_item_detail_transactions]" UpdateCommand="UPDATE [tbl_item_detail_transactions] SET [item_number] = @item_number, [item_description] = @item_description, [item_unit] = @item_unit, [item_quantity] = @item_quantity, [item_price] = @item_price, [item_amount] = @item_amount, [voucher_number] = @voucher_number WHERE [transaction_id] = @transaction_id">
            <DeleteParameters>
                <asp:Parameter Name="transaction_id" Type="Int32" />
            </DeleteParameters>
            <InsertParameters>
                <asp:Parameter Name="item_number" Type="Int32" />
                <asp:Parameter Name="item_description" Type="String" />
                <asp:Parameter Name="item_unit" Type="Int32" />
                <asp:Parameter Name="item_quantity" Type="Int32" />
                <asp:Parameter Name="item_price" Type="Int32" />
                <asp:Parameter Name="item_amount2" Type="Int32" />
                <asp:Parameter Name="voucher_number" Type="Int32" />
            </InsertParameters>
            <UpdateParameters>
                <asp:Parameter Name="item_number" Type="Int32" />
                <asp:Parameter Name="item_description" Type="String" />
                <asp:Parameter Name="item_unit" Type="Int32" />
                <asp:Parameter Name="item_quantity" Type="Int32" />
                <asp:Parameter Name="item_price" Type="Int32" />
                <asp:Parameter Name="item_amount" Type="Int32" />
                <asp:Parameter Name="voucher_number" Type="Int32" />
                <asp:Parameter Name="transaction_id" Type="Int32" />
            </UpdateParameters>
        </asp:SqlDataSource>

<script src="Scripts/jquery-1.8.2.js"></script>
<script src="Scripts/jquery-1.4.1.min.js"></script>

 <script type="text/javascript">
    $(function () {
        $("#ASPxGridView1").find("input[title='item_quantity']").blur(function () {
            var item_quantity = $(this).val();
            var item_price = $("#ASPxGridView1").find("input[title='item_price']").val();
            if (item_quantity != "" && item_price != "") {
                var total = parseInt(item_price) + parseInt(item_quantity);
                $("#ASPxGridView1").find("input[title='item_amount']").val(total);
            } else {
                $("#ASPxGridView1").find("input[title='item_amount']").val("");
            }
        })
    })
</script>