Detailed explanation of paging and SqlHelper class usage examples in php

This article mainly introduces the usage of paging and SqlHelper classes in PHP, and analyzes the definitions and specific usage techniques of PHP database query classes and paging classes in the form of examples. Friends in need can refer to it

The details are as follows :

The document directory structure is as follows:

The SqlHelper.php code is as follows:

<?php
/**
 * Created by JetBrains PhpStorm.
 * User: lee
 * Date: 13-7-26
 * Time: 下午8:30
 * To change this template use File | Settings | File Templates.
 */
class SqlHelper{
  private $mysqli;
  private static $host="localhost";
  private static $user="root";
  private static $pwd="";
  private static $db="world";
  private $sql=false;
  private $result=false;
  function __construct(){
    $this->mysqli=new MySQLi(self::$host,self::$user,self::$pwd,self::$db);
    if($this->mysqli->connect_error){
      die("连接数据库失败！ ".$this->mysql->connect_error);
    }
    $this->mysqli->query("set names utf8");
  }
  function execute_dql_all($sql){
    //执行查询语句
    $arr=array();
    $this->result=$this->mysqli->query($sql) or die ($this->mysql->connect_error);
    //将数据转存到$arr数组中
    while($row=mysqli_fetch_array($this->result,MYSQL_BOTH)){
      $arr[]=$row;
    }
    $this->result->free();
    return $arr;
  }
  function execute_dql_num($sql){
    //执行查询语句
    $arr=array();
    $this->result=$this->mysqli->query($sql) or die ($this->mysql->connect_error);
    //将数据转存到$arr数组中
    while($row=mysqli_fetch_array($this->result,MYSQLI_NUM)){
      $arr[]=$row;
    }
    $this->result->free();
    return $arr;
  }
  function execute_dql_assoc($sql){
    //执行查询语句
    $arr=array();
    $this->result=$this->mysqli->query($sql) or die ($this->mysql->connect_error);
    //将数据转存到$arr数组中
    while($row=mysqli_fetch_array($this->result,MYSQLI_ASSOC)){
      $arr[]=$row;
    }
    $this->result->free();
    return $arr;
  }
  //查询某表中的记录数
  function execute_dql_counts($table,$id="*"){
    $this->sql="select count($id) from $table";
    $this->result=$this->mysqli->query($this->sql);
    $row=mysqli_fetch_all($this->result);
    $this->result->free();
    return $row[0][0];
  }
  function execute_dml($sql){
    //执行正删改
    $this->result=$this->mysqli->query($sql);
    if(!$this->result){
      return -1;//执行正删改失败
    }else{
      if($this->mysqli->affected_rows>0){
        return 1;//执行正删改成功，影响行数
      }else{
        return 0;//执行正删改成功，但没有影响行数
      }
    }
  }
}

Paging.php code is as follows:

<?php
/**
 * Created by JetBrains PhpStorm.
 * User: lee
 * Date: 13-7-27
 * Time: 下午2:48
 * To change this template use File | Settings | File Templates.
 */
header("Content-type:text/html;charset=utf-8;");
require_once("SqlHelper.php");
class Paging {
  private $sqlHelper=false;
  private $pageCount=false;//页数
  private $counts=false;//总记录数
  private $returnArr=false;//分页超链接的分页
  function __construct(){
    $this->sqlHelper=new SqlHelper();
    $this->returnArr=array();
  }
  /*
   * 参数说明
   *
   * $table 分页时对那个表的数据分页
   * $id 辅助查询当前分页的数据表的总记录数
   * $pageSize 每页显示多少条信息记录数
   * $pagingSize 分页栏每次循环显示出来的个数
   * $nowPage 当前是第几页，默认第一页
   * $href 分页栏的超链接将要往哪里连接
   */
  function paging_prev_next($table,$id="*",$pageSize,$pagingSize,$nowPage=1,$href){
    $this->counts=$this->sqlHelper->execute_dql_counts($table,$id);
    $this->pageCount=ceil($this->counts/$pageSize);
    $this->returnArr["count"]=$this->counts;
    $this->returnArr["start"]=($nowPage-1)*$pageSize;
    $this->returnArr["limit"]=$pageSize;
    if($nowPage>$this->pageCount || $nowPage<=0){
      return false;
    }
    $t=(ceil($nowPage/$pagingSize)-1)*$pagingSize+1;
    $pre=$nowPage-$pagingSize;
    $nex=$nowPage+$pagingSize;
    echo "
      <span class=&#39;paging-list-a paging-list-a-withBg&#39;>{$nowPage}/{$this->pageCount}</span>
      <a href=&#39;{$href}?nowPage={$pre}&#39; class=&#39;paging-list-a&#39;><</a>";
    for($i=$t;$i<$t+$pagingSize;$i++){
      if($i*$pageSize>$this->pageCount*$pageSize){
        break;
      }else{
        if($nowPage==$i){
          echo "
          <a href=&#39;{$href}?nowPage={$i}&#39; class=&#39;paging-list-a paging-list-a-withBg&#39;>{$i}</a>";
        }else{
          echo "
          <a href=&#39;{$href}?nowPage={$i}&#39; class=&#39;paging-list-a&#39;>{$i}</a>";
        }
      }
    }
    echo "
      <a href=&#39;{$href}?nowPage={$nex}&#39; class=&#39;paging-list-a&#39;>></a>";
    return $this->returnArr;
  }
}

paging-list-link.css code is as follows:

/**
 * Created by JetBrains PhpStorm.
 * User: lee
 * Date: 13-7-27
 * Time: 下午5:56
 * To change this template use File | Settings | File Templates.
 */
.paging-list-a{
  border:1px solid #b5b5af;
  background-color:#efebed;
  font-family: 'Meiryo UI';
  font-size: 16px;
  font-weight: 600;
  padding: 0px 8px 0px 8px;
  /*cursor: pointer;*/
  text-decoration: none;
  color: #292927;
}
.paging-list-a-withBg{
  background-color: #1D92E2;
  color: white;
}

usePaging.php code is as follows:

<!DOCTYPE html>
<html>
<head>
  <title></title>
  <link rel="stylesheet" type="text/css" href="paging-list-link.css">
</head>
<body>
<?php
header("Content-type:text/html;charset=utf-8;");
require_once &#39;Paging.php&#39;;
$paging=new Paging();
//参数说明
/*
 * $table 分页时对那个表的数据分页
 * $id 辅助查询当前分页的数据表的总记录数
 * $pageSize 每页显示多少条信息记录数
 * $pagingSize 分页栏每次循环显示出来的个数
 * $nowPage 当前是第几页，默认第一页
 * $href 分页栏的超链接将要往哪里连接，当前页链接地址
 */
//控制起始页为
$nowPage=1;
if(isset($_GET["nowPage"])){
  $nowPage=$_GET["nowPage"];
}
//定义分页所需参数
$meiyexiansi=10;
$meiyelianjieshu=10;
$receiveArr=array();
$receiveArr=$paging->paging_prev_next("city","ID",$meiyexiansi,$meiyelianjieshu,$nowPage,"usePaging.php");
//容错判断
if(!$receiveArr){
  return;
}
//查询每页需要显示的数据，大小限制存在 $receiveArr 数组中
$sqlHelper=new SqlHelper();
$result=$sqlHelper->execute_dql_num("select * from city limit ".$receiveArr[&#39;start&#39;].",".$receiveArr[&#39;limit&#39;]."");
echo "<pre class="brush:php;toolbar:false">";
print_r($result);
echo "

"; ?>

The database used is the world database that comes with MySQL5.6

The following is a screenshot of the running effect:

But there is still a bug in the code. It is just that when the page is turned to the end, it will not be displayed. The reason is that there is a problem with the judgment around lines 41~43 of the Paging.php file.

The error code is as follows:

if($nowPage>$this->pageCount || $nowPage<=0){
  return false;
}

##The above is the entire content of this article, I hope it will be helpful to everyone's study.

Related recommendations:

PHP implementation of array paging method

php redis method to implement registration, deletion, editing, paging, login, follow and other functions

php simple implementationPagingQuery method

The above is the detailed content of Detailed explanation of paging and SqlHelper class usage examples in php. For more information, please follow other related articles on the PHP Chinese website!