原生的搜索分页

<?phpheader('content-type:text/html;charset=utf-8');//连接数据库$link=mysqli_connect('127.0.0.1','root','root','exam');//设置字符集mysqli_query($link,'set names utf8');$search=isset($_GET['search'])?$_GET['search']:""; //查询数据总条数$sql1="select count(*) num from rikao_15 where c_mingcheng like '%$search%'";$res1=mysqli_query($link,$sql1);$arr1=mysqli_fetch_assoc($res1);//获得数据总条数$size=$arr1['num'];//设置每页条数$length=3;//计算总页数$pages=ceil($size/$length);//传递页数$page=isset($_GET['page'])?$_GET['page']:1;//上一页，下一页$last=$page-1<1?1:$page-1;$next=$page+1>$pages?$pages:$page+1;//偏移量 $offset=($page-1)*$length;//写sql语句    $sql="select * from rikao_15 where c_mingcheng like '%$search%' limit $offset,$length " ;//执行     $res=mysqli_query($link,$sql); ?><center><div id='div1'><input type="search" name="search" value="<?php echo $search?>"><button onclick="page(1)">搜索</button><table border=1><tr><td>全选<input type="checkbox" name="quanxuan" onclick="quanxuan()"></td><td>自动序号</td><td>序列</td><td>名称</td><td>图片</td><td>作者</td><td>描述</td><td>权限</td><td>特定信息</td><td>操作</td></tr><?phpwhile($arr=mysqli_fetch_assoc($res)){?><tr><td><input type="checkbox" name="box"value="<?php echo $arr['id']?>"></td><td><?php echo $arr['id']?></td><td><?php echo $arr['id']?></td><td><?php echo $arr['c_mingcheng']?></td><td><img src="<?php echo $arr['c_filename']?>" alt="" width=150/></td><td><?php echo $arr['c_author']?></td><td><?php echo $arr['c_desc']?></td><td><?php        if($arr['c_quanxuan']==1){          echo '是';}else{echo '否';}   ?></td><td><?php echo $arr['c_infor']?></td><td><a href="javascript:del(<?php echo $arr['id']?>)">删除</a>  <?php        if($arr['c_quanxuan']==1){?><a href="upload.php?id=<?php echo $arr['c_filename']?>">下载</a><?php    }else{    ?><a href="javascript:fun1()">下载</a>    <?php}    ?></td></tr><?php}?><tr><td>全选<input type="checkbox" name="xuan" onclick="xuan()" ></td><td colspan=9><button onclick="Quan()">全选</button><button onclick="Fan()">反选</button><button onclick="Bu()">全不选</button><button onclick="Pi()">批量删除</button><button onclick="Tian()">添加</button></td></tr></table><a href="javascript:page(1)">首页</a><a href="javascript:page(<?php echo $last?>)">上一页</a><a href="javascript:page(<?php echo $next?>) ">下一页</a><a href="javascript:page(<?php echo $pages?>)">尾页</a>       <?php echo $page?>/<?php echo $pages?>   总共<?php echo $size?>条数据 </div></center><script type="text/javascript">function page(page){     var search = document.getElementsByName('search')[0].value; var ajax = new XMLHttpRequest();     ajax.open('get','ajax.php?page='+page+'&search='+search);         ajax.send();     ajax.onreadystatechange = function(){  if(ajax.readyState==4 &&ajax.status == 200){  document.getElementById('div1').innerHTML=ajax.responseText;}}}function del(id){     //var search = document.getElementsByName('search')[0].value; var ajax = new XMLHttpRequest();     ajax.open('get','del.php?id='+id);         ajax.send();     ajax.onreadystatechange = function(){  if(ajax.readyState==4 &&ajax.status == 200){          //alert(ajax.responseText); if(ajax.responseText==1){               alert('删除成功');   location.href='ajax.php'; }else{ alert('删除失败');   location.href='ajax.php'; } }}}/*function del(id){     //var search = document.getElementsByName('search')[0].value; var ajax = new XMLHttpRequest();     ajax.open('get','del.php?id='+id);         ajax.send();     ajax.onreadystatechange = function(){  if(ajax.readyState==4 &&ajax.status == 200){  //document.getElementById('div1').innerHTML=;  //alert(ajax.responseText);}}}*///上全选function quanxuan(){var quanxuan=document.getElementsByName('quanxuan')[0]var box=document.getElementsByName('box') for(var i=0;i<box.length;i++){    if(quanxuan.checked==true){           box[i].checked=true;}else{           box[i].checked=false;}}}//下全选function xuan(){var xuan=document.getElementsByName('xuan')[0]var box=document.getElementsByName('box') for(var i=0;i<box.length;i++){    if(xuan.checked==true){           box[i].checked=true;}else{           box[i].checked=false;}}}//全选按钮function Quan(){var box=document.getElementsByName('box') for(var i=0;i<box.length;i++){    box[i].checked=true;}}//全不选function Bu(){var box=document.getElementsByName('box') for(var i=0;i<box.length;i++){    box[i].checked=false;}}//反选function Fan(){var box=document.getElementsByName('box') for(var i=0;i<box.length;i++){    box[i].checked=!box[i].checked;}}//添加function Tian(){location.href='rikao.php';}//批量删除function Pi(){  var str="";  var box=document.getElementsByName('box')    for(var i=0;i<box.length;i++){      if(box[i].checked==true){           str=str+','+box[i].value;}}   str=str.substr(1);   var ajax = new XMLHttpRequest();     ajax.open('get','del.php?id='+str);         ajax.send();     ajax.onreadystatechange = function(){  if(ajax.readyState==4 &&ajax.status == 200){          //alert(ajax.responseText); if(ajax.responseText==1){               alert('删除成功');   location.href='ajax.php'; }else{ alert('删除失败');   location.href='ajax.php'; } }}  }function fun1(){  alert('该下载只支持会员');}</script>