How can move next page(using third party control) in grid view

<Behaviors>

                    <ig:Paging PagerAppearance="Bottom" PageSize="3" Enabled="true"></ig:Paging>

                    </Behaviors>

 protected void  grdUserTrainer_PageIndexChanged(object sender, PagingEventArgs e)

    {

        ShowGrid();

        getUserDetails(l_intLocationId, l_intCourseId, l_dtStartDate, l_dtEndDate, l_intTraineeStatus); 

        if (e.OldPageIndex > 0)

        {

            grdUserTrainer.Behaviors.Paging.PageIndex = e.OldPageIndex - 1;

        }

        else

        {

            grdUserTrainer.Behaviors.Paging.PageIndex = e.OldPageIndex + 1;

            

            grdUserTrainer.Behaviors.Paging.NextPageText = "next";

        }

Regards
Sekar.c