如何在同一页面上排序和显示结果，以及分页产品

Question

我正在努力建立一个电子商务网站，如果用户选择类似家用电器的类别，他将被重定向到一个列出所有家用电器的页面。 我想要的是，在他根据产品排序之前，用户将被显示所有的应用程序。我在这里使用输入代码

 $cat=1;
       if(isset($_POST['submit'])){

         $uni_id=$_POST['uni_name'];
         $col_id=$_POST['col_name'];
         $semester=$_POST['semester'];
        $result_per_page=5;
         $get_book="SELECT * FROM visitor_ad WHERE category=$cat AND university=$uni_id AND college=$col_id AND semester=$semester";
         $result=mysqli_query($link,$get_book) or die("cannot query database");
         $no_of_result=mysqli_num_rows($result);
        $no_of_pages=ceil($no_of_result/$result_per_page);
    if(!isset($_GET['pagea'])){

        $pagea=1;

    }
    else{
        $pagea=$_GET['pagea'];
    }

    $this_page_start=($pagea-1)*$result_per_page;
     $get_book="SELECT * FROM visitor_ad WHERE category=$cat AND university=$uni_id AND college=$col_id AND semester=$semester LIMIT ".$this_page_start.','.$result_per_page;
         $result=mysqli_query($link,$get_book) or die("cannot query database");
    while($row=mysqli_fetch_array($result)){
        $id=$row['id'];
        $title=$row['title'];
        $price=$row['price'];
        $phone=$row['phone'];
        $timestamp = strtotime($row['time']);
        $date = date('d-m-Y', $timestamp);
        $time = time('H:s', $timestamp);
        $photo=$row['photo'];
        $col_id=$row['college'];
        $uni_id=$row['university'];
        ?>
         <div id="list_show">

       <div id="list_img">
       <img src="<?php echo"../images/Ad_images/$photo" ?>" style="border:0px solid white;width:125px; height:140px; ">
       </div>
       <div id="list_con">
       <p><span id="list_title"> &#8377;<?php echo"$price"; ?>  </span><a href="tel:<?php echo"$phone "; ?>"><span id="list_phone"><img src="../images/siteimages/phone.png"><?php echo"$phone "; ?> </span></a>
       <p>Posted on:<?php echo"$date" ?> </p>
       <h1><?php echo"$title"; ?> </h1>

       </div>


       </div>

       <?php 
    }
    ?>

    <div id="plink">
    <?php
    if(!isset($_GET['pagea'])){
        $pagea=1;

    }
    else{
        $pagea=$_GET['pagea'];
    }
    $pageb=$pagea-1;
    if($pagea!=1){
        echo'<a href="books.php?page='.$pageb.'">&#xab;Back</a>';

    }


    for($pagea=1;$pagea<=$no_of_pages;$pagea++){

        echo'<a href="books.php?pagea='.$pagea.'">'.$pagea.'</a>';

    }

    if(!isset($_GET['pagea'])){
        $pagea=1;

    }
    else{
        $pagea=$_GET['pagea'];
    }

    $pagen=$pagea+1;
    if($pagea<$no_of_pages){
    echo'<a href="books.php?pagea='.$pagen.'">Next page&#xbb;</a>';
    }   

       }

       else{
         $result_per_page=5;
         $get_book="SELECT * FROM visitor_ad WHERE category=$cat";
         $result=mysqli_query($link,$get_book) or die("cannot query database");
         $no_of_result=mysqli_num_rows($result);
        $no_of_pages=ceil($no_of_result/$result_per_page);
    if(!isset($_GET['page'])){
        $page=1;

    }
    else{
        $page=$_GET['page'];
    }

    $this_page_start=($page-1)*$result_per_page;
     $get_book="SELECT * FROM visitor_ad WHERE category=$cat LIMIT ".$this_page_start.','.$result_per_page;
         $result=mysqli_query($link,$get_book) or die("cannot query database");
    while($row=mysqli_fetch_array($result)){
        $id=$row['id'];
        $title=$row['title'];
        $price=$row['price'];
        $phone=$row['phone'];
        $timestamp = strtotime($row['time']);
        $date = date('d-m-Y', $timestamp);
        $time = time('H:s', $timestamp);
        $photo=$row['photo'];
        $col_id=$row['college'];
        $uni_id=$row['university'];
        ?>
         <div id="list_show">

       <div id="list_img">
       <img src="<?php echo"../images/Ad_images/$photo" ?>" style="border:0px solid white;width:125px; height:140px; ">
       </div>
       <div id="list_con">
       <p><span id="list_title"> &#8377;<?php echo"$price"; ?>  </span><a href="tel:<?php echo"$phone "; ?>"><span id="list_phone"><img src="../images/siteimages/phone.png"><?php echo"$phone "; ?> </span></a>
       <p>Posted on:<?php echo"$date" ?> </p>
       <h1><?php echo"$title"; ?> </h1>

       </div>


       </div>

       <?php 
    }
    ?>

    <div id="plink">
    <?php
    if(!isset($_GET['page'])){
        $page=1;

    }
    else{
        $page=$_GET['page'];
    }
    $pageb=$page-1;
    if($page!=1){
        echo'<a href="books.php?page='.$pageb.'">&#xab;Back</a>';

    }


    for($page=1;$page<=$no_of_pages;$page++){

        echo'<a href="books.php?page='.$page.'">'.$page.'</a>';

    }

    if(!isset($_GET['page'])){
        $page=1;

    }
    else{
        $page=$_GET['page'];
    }

    $pagen=$page+1;
    if($page<$no_of_pages){
    echo'<a href="books.php?page='.$pagen.'">Next page&#xbb;</a>';
    }
    }

我能够做到这一点，但我也使用php显示每页显示10个产品，问题是当我排序时没有。结果和页面创建是正确的，但是当我浏览它时，显示所有结果而不进行排序。