Gridview Paging

protected void ChangeIndex1(object sender, GridViewPageEventArgs e)
    {
        GridView1.PageIndex = e.NewPageIndex;
        DataSet ds = DEBLOBJ.USERREQSEARCHDATE(LPOBJ);
        GridView1.DataSource = ds;
        GridView1.DataBind();
    }

    public void LoadGrid()
    {      
       DataSet ds = DEBLOBJ.USERREQSEARCHDATE(LPOBJ);
        GridView1.DataSource = ds;
        GridView1.DataBind();
    }

protected void ChangeIndex(object sender, GridViewPageEventArgs e)
    {
        GridView1.PageIndex = e.NewPageIndex;      
        GridView1.DataSource = Session["myvalue"];
        GridView1.DataBind();
    }

    public void LoadGrid()
    {
        DataSet ds = DEBLOBJ.GetYPUserReqDetails();
        Session["myvalue"] = ds;
        //HttpCookie mycookie = new HttpCookie("Venkat");
       // mycookie.Value =Convert.ToString(ds);
        UserReqDetailsGrid.DataSource = Session["myvalue"];
        UserReqDetailsGrid.DataBind();
    }