ThinkPHP implements paging function

<?php
//The name of the namespace is the same as the previous directory tools//Reason: The current class file will be introduced by the automatic loading mechanism// At the same time, "tools" will be turned into the file's superior directory, and then the Page file will be obtainednamespace Tools;

class Page {
  private $total; //Total records in the data table  private $listRows; //The number of rows displayed per page  private $limit;
  private $uri;  //Current link URL  private $pageNum; //Page number  private $config=array('header'=>"Records", "prev"=>"Previous Page", "next"=>"Next Page", "first"=>"front page", "last"=>"Last Page");
  private $listNum=8; //Limit the number of page numbers list  
  /*
    * $total Total records
    * $listRows Number of rows displayed per page
    */
  public function __construct($total, $listRows=10, $pa=""){
    $this->total=$total;  //Total records in the data table    $this->listRows=$listRows; //Set the number of rows displayed per page    $this->uri=$this->getUri($pa); //Request address    $this->page=!empty($_GET["page"]) ? $_GET["page"] : 1; //Current page    $this->pageNum=ceil($this->total/$this->listRows); //Total page count    $this->limit=$this->setLimit(); //Limit the length per page  }

  private function setLimit(){
    return "Limit ".($this->page-1)*$this->listRows.", {$this->listRows}";
  }

  //Request address  private function getUri($pa){
    $url=$_SERVER["REQUEST_URI"].(strpos($_SERVER["REQUEST_URI"], '?')?'':"?").$pa;
    $parse=parse_url($url);

  

    if(isset($parse["query"])){
      parse_str($parse['query'],$params);
      unset($params["page"]);
      $url=$parse['path'].'?'.http_build_query($params);
      
    }

    return $url;
  }

  function __get($args){
    if($args=="limit")
      return $this->limit;
    else
      return null;
  }

  //Which one is displayed on the start page  private function start(){
    if($this->total==0)
      return 0;
    else
      return ($this->page-1)*$this->listRows+1;
  }

  // Which one ends from  private function end(){
    return min($this->page*$this->listRows,$this->total);
  }

  //Home page hyperlink  private function first(){
    $html = "";
    if($this->page==1)
      $html.='';
    else
      $html.="  <a href='{$this->uri}&page=1'>{$this->config["first"]}</a>  ";

    return $html;
  }

  //Previous page  private function prev(){
    $html = "";
    if($this->page==1)
      $html.='';
    else
      $html.="  <a href='{$this->uri}&page=".($this->page-1)."'>{$this->config["prev"]}</a>  ";

    return $html;
  }

  //Page number list hyperlink  private function pageList(){
    $linkPage="";
    
    $inum=floor($this->listNum/2);
  
    for($i=$inum; $i>=1; $i--){
      $page=$this->page-$i;

      if($page<1)
        continue;

      $linkPage.=" <a href='{$this->uri}&page={$page}'>{$page}</a> ";

    }
  
    $linkPage.=" {$this->page} ";
    

    for($i=1; $i<=$inum; $i++){
      $page=$this->page+$i;
      if($page<=$this->pageNum)
        $linkPage.=" <a href='{$this->uri}&page={$page}'>{$page}</a> ";
      else
        break;
    }

    return $linkPage;
  }

  //Next page  private function next(){
    $html = "";
    if($this->page==$this->pageNum)
      $html.='';
    else
      $html.="  <a href='{$this->uri}&page=".($this->page+1)."'>{$this->config["next"]}</a>  ";

    return $html;
  }

  //Last page  private function last(){
    $html = "";
    if($this->page==$this->pageNum)
      $html.='';
    else
      $html.="  <a href='{$this->uri}&page=".($this->pageNum)."'>{$this->config["last"]}</a>  ";

    return $html;
  }

  //Jump  private function goPage(){
    return '  <input type="text" onkeydown="javascript:if(==13){var page=(>'.$this->pageNum.')?'.$this->pageNum.':;location=\''.$this->uri.'&page=\'+page+\'\'}" value="'.$this->page.'" style="width:25px"><input type="button" value="GO" onclick="javascript:var page=(>'.$this->pageNum.')?'.$this->pageNum.':;location=\''.$this->uri.'&page=\'+page+\'\'">  ';
  }

  //Page Number List  function fpage($display=array(0,1,2,3,4,5,6,7,8)){
    $html[0]="  There are a total of<b>{$this->total}</b>{$this->config["header"]}  ";
    $html[1]="&nbsp;&nbsp;Show per page<b>".($this-&gt;end()-$this-&gt;start()+1)."&lt;/b&gt;strip，This page&lt;b&gt;{$this-&gt;start()}-{$this-&gt;end()}&lt;/b&gt;strip&amp;nbsp;&amp;nbsp;";
    $html[2]="&amp;nbsp;&amp;nbsp;&lt;b&gt;{$this-&gt;page}/{$this-&gt;pageNum}&lt;/b&gt;Page&amp;nbsp;&amp;nbsp;";
    
    $html[3]=$this-&gt;first();
    $html[4]=$this-&gt;prev();
    $html[5]=$this-&gt;pageList();
    $html[6]=$this-&gt;next();
    $html[7]=$this-&gt;last();
    $html[8]=$this-&gt;goPage();
    $fpage='';
    foreach($display as $index){
      $fpage.=$html[$index];
    }

    return $fpage;

  }


}

//Product List  function showlist(){

   //Implement paging effect   $goods = D('goods');

   //① Total number of records obtained for data   $total = $goods -> count(); //select count(*) from sw_goods;
   $per = 7; // Show 7 records per page
   //②Instantiate the paging class   $page_obj = new \Tools\Page($total, $per);

   //③Custom sql statements to obtain information per page   $sql = "select * from sw_goods order by goods_id desc ".$page_obj->limit;
   $info = $goods->query($sql);

   //④ Get the page number list   $pagelist = $page_obj->fpage(array(3,4,5,6,7,8));

   //distribute   $this->assign('pagelist',$pagelist);
   $this->assign('info',$info);
   $this->display();
  }