Home  >  Article  >  Backend Development  >  Paging source and paging class in php_PHP tutorial

Paging source and paging class in php_PHP tutorial

WBOY
WBOYOriginal
2016-07-13 17:14:291425browse

The so-called paging display means that the result set in the database is artificially divided into sections for display. Two initial parameters are required here: How many records per page ($PageSize)?

What page is the current page ($CurrentPageID)?
Now just give me another result set and I can display a specific result.
As for other parameters, such as: previous page ($PReviousPageID), next page ($NextPageID), total number of pages ($numPages), etc., they can all be obtained based on the previous things.
Taking the MySQL database as an example, if you want to intercept a certain piece of content from the table, the sql statement can be used: select * from table limit offset, rows. Take a look at the following set of SQL statements and try to find the rules.
The first 10 records: select * from table limit 0,10
Records 11 to 20: select * from table limit 10,10
Records 21 to 30: select * from table limit 20,10

This set of sql statements is actually the sql statement for fetching data from each page of the table when $PageSize=10. We can summarize such a template:
select * from table limit ($CurrentPageID – 1) * $PageSize, $PageSize
Take this template and substitute the corresponding values ​​​​into the above set of SQL statements to see if that is the case. After solving the most important problem of how to obtain the data, all that is left is to pass the parameters, construct the appropriate SQL statement and then use PHP to obtain the data from the database and display it. Below I will explain it with specific code.
3. Simple code
Please read the following code in detail, debug and run it yourself, it is best to modify it and add your own functions, such as search, etc.
[php]

The code is as follows Copy code
 代码如下 复制代码

// 建立数据库连接
$link = mysql_connect(“localhost”, “mysql_user”, “mysql_passWord”)
or die(“Could not connect: ” . mysql_error());
// 获取当前页数
if( isset($_GET['page']) ){
$page = intval( $_GET['page'] );
}
else{
$page = 1;
}
// 每页数量
$PageSize = 10;
// 获取总数据量
$sql = “select count(*) as amount from table”;
$result = mysql_query($sql);
$row = mysql_fetch_row($result);
$amount = $row['amount'];
// 记算总共有多少页
if( $amount ){
if( $amount < $page_size ){ $page_count = 1; } //如果总数据量小于$PageSize,那么只有一页
if( $amount % $page_size ){ //取总数据量除以每页数的余数
$page_count = (int)($amount / $page_size) + 1; //如果有余数,则页数等于总数据量除以每页数的结果取整再加一
}else{
$page_count = $amount / $page_size; //如果没有余数,则页数等于总数据量除以每页数的结果
}
}
else{
$page_count = 0;
}
// 翻页链接
$page_string = ”;
if( $page == 1 ){
$page_string .= ‘第一页|上一页|’;
}
else{
$page_string .= ‘第一页|上一页|’;
}
if( ($page == $page_count) || ($page_count == 0) ){
$page_string .= ‘下一页|尾页’;
}
else{
$page_string .= ‘下一页|尾页’;
}
// 获取数据,以二维数组格式返回结果
if( $amount ){
$sql = “select * from table order by id desc limit “. ($page-1)*$page_size .”, $page_size”;
$result = mysql_query($sql);

while ( $row = mysql_fetch_row($result) ){
$rowset[] = $row;
}
}else{
$rowset = array();
}
// 没有包含显示结果的代码,那不在讨论范围,只要用foreach就可以很简单的用得到的二维数组来显示结果
?>

// Establish database connection<🎜> $link = mysql_connect(“localhost”, “mysql_user”, “mysql_passWord”)<🎜> or die(“Could not connect: ” . mysql_error());<🎜> // Get the current page number <🎜> if( isset($_GET['page']) ){<🎜> $page = intval( $_GET['page'] );<🎜> }<🎜> else{<🎜> $page = 1;<🎜> }<🎜> //Number per page<🎜> $PageSize = 10;<🎜> // Get the total data volume <🎜> $sql = “select count(*) as amount from table”;<🎜> $result = mysql_query($sql);<🎜> $row = mysql_fetch_row($result);<🎜> $amount = $row['amount'];<🎜> // Calculate how many pages there are in total <🎜> if( $amount ){<🎜> if ($ amount & lt; $ page_size) {$ page_count = 1;} // If the total data amount is less than $ pageSize, then there is only one page <🎜> if( $amount % $page_size ){                                                                                                                                                   $page_count = (int)($amount / $page_size) + 1;                        //If there is a remainder, the number of pages is equal to the total data amount divided by the number of pages, rounded up and plus one <🎜> }else{<🎜> $ page_count = $ amount /$ page_size; // If there is no more number, the number of pages is equal to the total data volume divided by the results of each page <🎜> }<🎜> }<🎜> else{<🎜> $page_count = 0;<🎜> }<🎜> // Page turning link<🎜> $page_string = ”;<🎜> if( $page == 1 ){<🎜> $page_string .= ‘First page|Previous page|’;<🎜> }<🎜> else{<🎜> $page_string .= 'First page|Previous page|'; } if( ($page == $page_count) || ($page_count == 0) ){ $page_string .= ‘next page|last page’; } else{ $page_string .= 'Next page| Last page'; } // Get data and return the result in two-dimensional array format if( $amount ){ $sql = “select * from table order by id desc limit “. ($page-1)*$page_size .”, $page_size”; $result = mysql_query($sql); while ( $row = mysql_fetch_row($result) ){ $rowset[] = $row; } }else{ $rowset = array(); } // There is no code to display the results, so that is beyond the scope of discussion. You can simply use the obtained two-dimensional array to display the results using foreach ?>

PHP paginator production, automatically generates faceted page numbers, JS calls functions

The code is as follows Copy code

class PageView{
/**page number**/
Public $pageNo = 1;
/**Page size**/
Public $pageSize = 20;
/**How many pages in total**/
Public $pageCount = 0;
/**Total number of records**/
Public $totalNum = 0;
/**Offset, starting line of current page**/
Public $offSet = 0;
/**Data per page**/
Public $pageData = array();

/**Is there a previous page**/
Public $hasPrePage = true;
/**Is there a next page**/
Public $hasNextPage = true;

public $pageNoList = array();

public $jsFunction ='jsFunction';
/**
* *
* @param unknown_type $count total number of rows
* @param unknown_type $size paging size
* @param unknown_type $string
​​*/
Public function __construct($count=0, $size=20,$pageNo=1,$pageData =array(),$jsFunction='jsFunction'){

$this->totalNum = $count;//Total number of records
           $this->pageSize = $size;//Size of each page
            $this->pageNo = $pageNo;
//Calculate the total number of pages
           $this->pageCount = ceil($this->totalNum/$this->pageSize);
           $this->pageCount = ($this->pageCount<=0)?1:$this->pageCount;
//Check pageNo
           $this->pageNo = $this->pageNo == 0 ? 1 : $this->pageNo;
$this->pageNo = $this->pageNo > $this->pageCount? $this->pageCount : $this->pageNo;

//Calculate offset
$this->offset = ( $this->pageNo - 1 ) * $this->pageSize;
//Calculate whether there is a previous page or a next page
            $this->hasPrePage = $this->pageNo == 1 ?false:true;

$this->hasNextPage = $this->pageNo >= $this->pageCount ?false:true;

$this->pageData = $pageData;
            $this->jsFunction = $jsFunction;

    }
    /**
* Paging algorithm
* @return
​​*/
    private function generatePageList(){
        $pageList = array();
        if($this->pageCount <= 9){
            for($i=0;$i<$this->pageCount;$i++){
                array_push($pageList,$i+1);
            }
        }else{
            if($this->pageNo <= 4){
                for($i=0;$i<5;$i++){
                    array_push($pageList,$i+1);
                }
                array_push($pageList,-1);
                array_push($pageList,$this->pageCount);

            }else if($this->pageNo > $this->pageCount - 4){
                array_push($pageList,1);

                array_push($pageList,-1);
                for($i=5;$i>0;$i--){
                    array_push($pageList,$this->pageCount - $i+1);
                }
            }else if($this->pageNo > 4 && $this->pageNo <= $this->pageCount - 4){
                array_push($pageList,1);
                array_push($pageList,-1);

                array_push($pageList,$this->pageNo -2);
                array_push($pageList,$this->pageNo -1);
                array_push($pageList,$this->pageNo);
                array_push($pageList,$this->pageNo + 1);
                array_push($pageList,$this->pageNo + 2);

                array_push($pageList,-1);
                array_push($pageList,$this->pageCount);

            }
        }
        return $pageList;
    }

    /***
* Create paging control
* @param
* @return String
​*/
    public function echoPageAsDiv(){
        $pageList = $this->generatePageList();

        $pageString ="

");
        return $pageString;
    }
}

?>

PHP调用

 代码如下
 代码如下 复制代码


$pageNo = $_GET['pageNo'];
if(empty($pageNo)){
}
//分页数据
$pageData = News::getNewsPage($pageNo,$pageSize);
       //取得总行数
$count = News::getNewsCount();
        //创建分页器
$p = new PageView($count['0']['TOTAL'],$pageSize,$pageNo,$pageData);
     //生成页码
$pageViewString = $p->echoPageAsDiv();

复制代码
$pageNo = $_GET['pageNo'];

if(empty($pageNo)){

} $pageData = News::getNewsPage($pageNo,$pageSize);        //取得总行数 $count = News::getNewsCount();         //创建分页器 $p = new PageView($count['0']['TOTAL'],$pageSize,$pageNo,$pageData);      //生成页码 $pageViewString = $p->echoPageAsDiv();
http://www.bkjia.com/PHPjc/628968.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/628968.htmlTechArticle所谓分页显示,也就是将数据库中的结果集人为的分成一段一段的来显示,这里需要两个初始的参数:每页多少条记录($PageSize)? 当前是...
Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn