PHP基于面向对象封装的分页类示例

<?php  class Page  {    protected $num;//每页显示条数    protected $total;//总记录数    protected $pageCount;//总页数    protected $current;//当前页码    protected $offset;//偏移量    protected $limit;//分页页码    /**     * 构造方法     * @param int $total 总记录数     * @param int $num  每页显示条数     */    public function __construct($total,$num=5)    {      //1.每页显示条数      $this->num = $num;      //2.总记录数      $this->total = $total;      //3.总页数      $this->pageCount = ceil($total/$num);      //4.偏移量      $this->offset = ($this->current-1)*$num;      //5.分页页码      $this->limit = "{$this->offset},{$this->num}";      //6.初始化当前页      $this->current();    }    /**     * 初始化当前页     */    public function current(){      $this->current = isset($_GET['page'])?$_GET['page']:'1';      //判断当前页最大范围      if ($this->current>$this->pageCount){        $this->current = $this->pageCount;      }      //判断当前页最小范围      if ($this->current<1){        $this->current = 1;      }    }    /**     * 访问没权限访问的属性     * @param string $key 想访问的属性     * @return float|int|string 返回对应要改变的条件     */    public function __get($key){      if ($key == "limit") {        return $this->limit;      }      if ($key == "offset") {        return $this->offset;      }      if ($key == "current") {        return $this->current;      }    }    /**     * 处理分页按钮     * @return string 拼接好的分页按钮     */    public function show(){      //判断初始页码      $_GET['page'] = isset($_GET['page'])?$_GET['page']:'1';      //将$_GET值赋给上下变量      $first = $end = $prev = $next = $_GET;      // var_dump($prev);      //上一页      //判断上一页范围      if ($this->current-1<1){        $prev['page'] = 1;      }else{        $prev['page'] = $this->current-1;      }      //下一页      //判断下一页范围      if ($this->current+1>$this->pageCount) {        $next["page"] = $this->pageCount;      }else{        $next['page'] = $this->current+1;      }      /*      首页      $first['page'] = 1;       //尾页      $end['page'] = $this->pageCount;      */      //拼接路径      $url = "http://".$_SERVER["SERVER_NAME"].$_SERVER["SCRIPT_NAME"];      //拼接数组url地址栏后缀?传入参数      //http://xxx/xxx/Page.class.php?page=值      $prev = http_build_query($prev);      $next = http_build_query($next);      // $first = http_build_query($first);      // $end = http_build_query($end);      //拼接完整路径      $prevpath = $url."?".$prev;      $nextpath = $url."?".$next;      // $firstpath = $url."?".$first;      // $endpath = $url."?".$end;      $str = "共有{$this->total}条记录 共有{$this->pageCount}页 ";      $str .= "<a href='{$url}?page=1'>首页</a> ";      $str .= "<a href='{$prevpath}'>上一页</a> ";      $str .= "<a href='{$nextpath}'>下一页</a> ";      $str .= "<a href='{$url}?page={$this->pageCount}'>尾页</a> ";      return $str;    }  }  //自行调试  $a = new Page(10);  echo $a->show();?>