分页出问题拉。请看代码！（c#）

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.Mobile;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.MobileControls;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using Bean;
using Business;
public partial class wap_list : System.Web.UI.MobileControls.MobilePage
{
    DataSet dataset = new DataSet();
    NewBean strPage = new NewBean();    protected void Page_Load(object sender, EventArgs e)
    {
        if(!IsPostBack)
        {
            strPage.pageInfo = 1;
            Session["page"] = strPage.pageInfo;
            Response.Write("回发页");
        }
        else
        {
            try
            {
                //获得驱除HTML的内容
                DbtoNews db = new DbtoNews();
                int id = int.Parse(System.Configuration.ConfigurationSettings.AppSettings["id"]);
                dataset = db.getNew(id);
                for (int i = 0; i < dataset.Tables[0].Rows.Count; i++)
                {
                    string news = StripHTML.DeleteHTML(dataset.Tables[0].Rows[i][2].ToString());
                    dataset.Tables[0].Rows[i][2] = news;
                }
                //获得字符串
                strPage.str = dataset.Tables[0].Rows[0][2].ToString();
                //获得字符串总长度
                strPage.strLength = strPage.str.Length;
                //通过判断，获得一共能分多少页
                if (strPage.strLength % strPage.pageSize == 0)
                {
                    strPage.pageCount = strPage.strLength / strPage.pageSize;
                }
                else
                {
                    strPage.pageCount = strPage.strLength / strPage.pageSize + 1;
                }                //获得当前页
                strPage.pageInfo = int.Parse(Session["page"].ToString());
                this.Page(strPage.pageInfo);
                //绑定数据
                this.List1.DataSource = dataset.Tables[0].DefaultView;
                this.List1.DataMember = "news";
                this.List1.DataBind();
            }
            catch (Exception ex)
            {
                Response.Write(ex.Message.ToString());
            }
        }
    }
    protected void Command1_Click(object sender, EventArgs e)
    {
        //获得当前页
        strPage.pageInfo = int.Parse(Session["page"].ToString());
        if (strPage.pageInfo > 1)
        {
            strPage.pageInfo--;
            this.Page(strPage.pageInfo);
            //保存当前页
            Session["page"] = strPage.pageInfo;
        }
        else
        {
            strPage.pageInfo = 1;
            this.Page(strPage.pageInfo);
            //保存当前页
            Session["page"] = strPage.pageInfo;
        }
    }
    protected void Command2_Click(object sender, EventArgs e)
    {
        //获得当前页
        strPage.pageInfo = int.Parse(Session["page"].ToString());
        if (strPage.pageInfo < strPage.pageCount)
        {
            strPage.pageInfo++;
            this.Page(strPage.pageInfo);
            //保存当前页
            Session["page"] = strPage.pageInfo;
        }
        else
        {
            strPage.pageInfo = strPage.pageCount;
            this.Page(strPage.pageInfo);
            //保存当前页
            Session["page"] = strPage.pageInfo;
        }
    }
    public void Page(int pagenum)
    {
        //截取
        Response.Write("当前页"+ pagenum + "，");
        Response.Write("开始截取的长度" + (pagenum - 1) * strPage.pageSize + "。");
        if (pagenum < strPage.pageCount)
        {
            dataset.Tables[0].Rows[0][2] = strPage.str.Substring((pagenum - 1) * strPage.pageSize, strPage.pageSize);
        }
        else
        {
            dataset.Tables[0].Rows[0][2] = strPage.str.Substring((pagenum - 1) * strPage.pageSize, strPage.strLength - (pagenum - 1) * strPage.pageSize);
        }
    }
    protected void Form1_Activate(object sender, EventArgs e)
    {    }
}