PagedDataSource 分页问题

    public DataSet ds;
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!this.IsPostBack)
        {
            ds = new DataSet();
            GetDv();
            this.DataListBind();
        }
    }    private void GetDv() {
        string str = String.Empty;
        if (Request.QueryString["title"] == null)
            str = "";
        else
            str = Request.QueryString["title"].ToString();
        if (Request.QueryString["tablename"] != null)
            ds = YsnRx.dc.SelDoubleDelve(Convert.ToString(Request.QueryString["tablename"]), str);
    }    //绑定DataList
    private void DataListBind() {
        PagedDataSource pds = new PagedDataSource();
        pds.DataSource = ds.Tables["t_CompanyInfo"].DefaultView;
        pds.AllowPaging = true;
        pds.PageSize = 10;
        int CurPage;
        if (Request.QueryString["page"] != null)
            CurPage = Convert.ToInt32(Request.QueryString["page"]);
        else
            CurPage = 1;
        if (!pds.IsFirstPage)
        {
            first.NavigateUrl = Request.CurrentExecutionFilePath + "?page=" + 1;  首页link链接
            prev.NavigateUrl = Request.CurrentExecutionFilePath + "?page=" + Convert.ToString(CurPage - 1);    上一页link链接
        }
        if (!pds.IsLastPage)
        {
            end.NavigateUrl = Request.CurrentExecutionFilePath + "?page=" + pds.PageCount;  尾页link
            next.NavigateUrl = Request.CurrentExecutionFilePath + "?page=" + Convert.ToString(CurPage + 1);         下一页link链接
        }
        pds.CurrentPageIndex = CurPage - 1;
        Response.Write(Convert.ToString(pds.CurrentPageIndex));
        CurrentLbl.Text = CurPage.ToString();
        PageSum.Text = pds.PageCount.ToString();
        TotalLbl.Text = pds.DataSourceCount.ToString();
        DataList1.DataSource = pds;
        DataList1.DataBind();
    }加载时候有数据，会显示，但翻页就没数据了。自己感觉是title传值那边有问题，因为我后面转本页时候没传title,tablename值,但是DataSet不是会缓存吗？不可能每次访问都加载一次吧？请问怎么处理?