<script src="/js/jquery-1.4.1.js" type="text/javascript"></script>
   <script type="text/javascript">
       var pageindex = 1;
       var pagesize = 2;
       $(function () {
           previous();
       })
       function previous() {
           if (pageindex < 1 || pageindex == 1) {
               pageindex = 1;
               $("#imgdiv img:lt(" + pagesize + ")").show();
               $("#imgdiv img").not($("#imgdiv img:lt(" + pagesize + ")")).hide();
           }
           else {
               pageindex--;
               if (pageindex != 1) {
                   $("#imgdiv img:gt(" + ((pageindex - 1) * pagesize - 1) + "):lt(" + pagesize + ")").show();
                   $("#imgdiv img").not($("#imgdiv img:gt(" + ((pageindex - 1) * pagesize - 1) + "):lt(" + pagesize + ")")).hide();
               }
               if (pageindex == 1) {
                   $("#imgdiv img:lt(" + pagesize + ")").show();
                   $("#imgdiv img").not($("#imgdiv img:lt(" + pagesize + ")")).hide();
               }
           }
       }
       function next() {
           var p = $("#imgdiv img").length / pagesize;

           var pagecount = parseInt(Math.ceil(p));

           if (pageindex + 1 > pagecount) {
               pageindex = pagecount;
           } else {
               pageindex++;
           }
           $("#imgdiv img:gt(" + ((pageindex - 1) * pagesize - 1) + "):lt(" + pagesize + ")").show();
           $("#imgdiv img").not($("#imgdiv img:gt(" + ((pageindex - 1) * pagesize - 1) + "):lt(" + pagesize + ")")).hide();
       }
   </script>
<div>
       <a href="javascript:previous()">上一頁</a>
       <div id="imgdiv">
           <img src="/images/001.jpg" alt="第一頁的第一張"/>
           <img src="/images/002.jpg" />
           <img src="/images/003.jpg" />
           <img src="/images/004.jpg" />
           <img src="/images/005.jpg" /> 
       </div>
       <a href="javascript:next()">下一頁</a>
   </div>