/// <summary>
        /// 分页函数
        /// </summary>
        /// <param name="recordcount">总记录数</param>
        /// <param name="pagesize">每页记录数</param>
        /// <param name="currentpage">当前页数</param>
        /// <returns></returns>
        public static string HtmlPage(int recordcount, int pagesize, int currentpage)
        {
            string thisUrl = CreateUrl();
            string pageStr = "";
            int allcurrentpage = 0;
            int next = 0;
            int pre = 0;
            int startcount = 0;
            int endcount = 0;

            if (currentpage < 1) currentpage = 1;

            //计算总页数
            if (pagesize != 0)
            {
                allcurrentpage = (recordcount / pagesize);
                allcurrentpage = ((recordcount % pagesize) != 0 ? allcurrentpage + 1 : allcurrentpage);
                allcurrentpage = (allcurrentpage == 0 ? 1 : allcurrentpage);
            }
            next = currentpage + 1;
            pre = currentpage - 1;


            //中间页起始序号
            startcount = (currentpage + 5) > allcurrentpage ? allcurrentpage - 9 : currentpage - 4;

            //中间页终止序号
            endcount = currentpage < 5 ? 10 : currentpage + 5;

            //为了避免输出的时候产生负数，设置如果小于1就从序号1开始
            if (startcount < 1)
                startcount = 1;

            //页码+5的可能性就会产生最终输出序号大于总页码，那么就要将其控制在页码数之内
            if (allcurrentpage < endcount)
                endcount = allcurrentpage;

            //
            pageStr += currentpage > 1 ? "&nbsp;<a href=\"" + thisUrl + "&page=1\" title=\"首页\">首页</a>&nbsp;<a href=\"" + thisUrl + "&page=" + pre + "\" title=\"前页\">前页</a>" : "首页 前页";

            //if (startcount > 1) pageStr += currentpage > 1 ? "&nbsp;<a href=\"" + thisUrl + "&page=" + pre + "\" title=\"上一页\">上一页</a>" : "";

            //当页码数大于1时, 则显示页码
            if (endcount > 1)
            {
                //中间页处理, 这个增加时间复杂度，减小空间复杂度
                for (int i = startcount; i <= endcount; i++)
                {
                    pageStr += currentpage == i ? "&nbsp;" + i + "" : "&nbsp;<a href=\"" + thisUrl + "&page=" + i + "\" >" + i + "</a>";
                }
            }

            pageStr += currentpage != allcurrentpage ? "&nbsp;<a href=\"" + thisUrl + "&page=" + next + "\" title=\"后页\">后页</a>&nbsp;<a href=\"" + thisUrl + "&page=" + allcurrentpage + "\" title=\"尾页\">尾页</a>&nbsp;" : "后页 尾页";
            //if (endcount < allcurrentpage) pageStr += currentpage != allcurrentpage ? "&nbsp;<a href=\"" + thisUrl + "&page=" + next + "\" title=\"下一页\">下一页</a>&nbsp;" : "";


            if (endcount > 1)
                pageStr += "&nbsp;";

            pageStr += "&nbsp;页次：" + currentpage + "/" + allcurrentpage + " 页 " + pagesize + "个/页 ";

            pageStr += "<select name=topage onChange=\"javascript:location.href=this.options[selectedIndex].value\">";
            for (int i = 1; i <= allcurrentpage; i++)
            {
                pageStr += "<option value=\"" + thisUrl + "&page=&quo