前一陣子在逛逛yahoo的知識+的時候發現還不少人在問分頁的問題，我就來分享一下自己寫的分頁function吧
```php
function Pager($pager_options = [])
{
//因為無法使用可變變數取得$_開頭的超級全域變數，所以先利用參考的方式值到自定義的變數
$post = &$_POST;
$get = &$_GET;
$request = &$_REQUEST;
if (empty($pager_options['totalItems'])) {
die('未設置 totalItems');
}
//取得分頁變數的方式可為request、get、post
$method = (empty($pager_options['method'])) ? 'request' : $pager_options['method'];
$method = strtolower($method);
$method = $$method;
//取得分頁變數，例如pageVar為pageID，$method為post則分頁的變數則為$_POST['pageID']
$pageVar = (empty($pager_options['pageVar'])) ? 'pageID' : $pager_options['pageVar'];
//設定每頁幾筆
$pager_options['perPage'] = (empty($pager_options['perPage'])) ? 10 : $pager_options['perPage'];
//顯示同一個頁面顯示幾頁
$pager_options['delta'] = (empty($pager_options['delta'])) ? 10 : $pager_options['delta'];
//取得當前頁數
$pager_options['current'] = (empty($method[$pageVar])) ? 1 : $method[$pageVar];
//設定link的前置網址
$pager_options['link'] = (empty($pager_options['link'])) ? $_SERVER['PHP_SELF'] : $pager_options['link'];
//取得總筆數
$total = ceil($pager_options['totalItems'] / $pager_options['perPage']);
if ($pager_options['current'] > $total && $total != 0) {
$pager_options['current'] = $total;
}
$pager_options['page_numbers'] = [
'current' => $pager_options['current'],
'total' => $total,
];
$pager_options['deltaStart'] = floor(($pager_options['page_numbers']['current'] - 1) / $pager_options['delta']) * $pager_options['delta'] + 1;
$pager_options['start'] = ($pager_options['current'] - 1) * $pager_options['perPage'];
$pager_options['offset'] = $pager_options['perPage'];
$pager_options['from'] = $pager_options['start'] + 1;
$pager_options['to'] = $pager_options['from'] + $pager_options['perPage'] - 1;
return $pager_options;
}
//改利用Pager做查詢會幫你完成分頁
//可用參數
/*
perPage 每頁幾筆
delta 顯示頁數
link a標籤上的連結
pageVar 分頁的參數
method 取得頁數變數的方法可以為post,get,request
totalItems 總筆數
*/
$page = Pager([
'perPage' => 10,
'delta' => 10,
'link' => 'index.php?op=default',
'pageVar' => 'page',
'totalItems' => 100,
]);
var_dump($page);
//回傳的參數
/*
$page['perPage']; 每頁幾筆
$page['delta']; 顯示頁數
$page['link']; a標籤上的連結
$page['totalItems']; 總筆數
$page['page_numbers']['current']; 目前所在頁數
$page['page_numbers']['total']; 總頁數
$page['deltaStart'];
$page['start']; mysql limit的start值
$page['offset']; mysql limit的offset值
$page['from'];
$page['to'];
*/
```
原則上這個分頁是我從之前寫的程式抽出來的，原本是和phplib的db物件做結合，當然了，也可以拿去和其他的DB物件做結合，看大家怎麼變化囉
```php
//載入phplib的db物件
require_once dirname(__FILE__).'/../phplib/db_mysql.inc';
//為db物件增加method並增加修改語系問題
class MySQL extends DB_MySQL
{
/* public: connection parameters */
public $Host = DBLOCATION;
public $Database = DBNAME;
public $User = DBUSER;
public $Password = DBPW;
public function query($sql)
{
//在每次查詢時先送出定義mysql語系的語法，如果是mysql4.0以下的話請把這一段拿掉
parent::query('set names utf8');
return parent::query($sql);
}
//取得總筆數
public function getTotalItems($sql)
{
//正規表示將select語法改為 select count(*) from table
$countSql = preg_replace('/(ORDER|LIMIT)(.*)/i', '', $sql);
$count_pattern = '/SELECT\s(.*)\sfrom\s/imsU';
if (preg_match($count_pattern, $countSql, $matched)) {
$groupby_pattern = '/(GROUP\s?BY(.*))/ism';
if (preg_match($groupby_pattern, $countSql, $matched2)) {
$countSql = str_replace($matched2[1], '', $countSql);
$countSql = str_replace($matched[1], sprintf('COUNT(DISTINCT %s) as totalItems', $matched2[2]), $countSql);
} else {
$countSql = str_replace($matched[1], 'COUNT(*) as totalItems', $sql);
}
$this->query($countSql);
$this->next_record();
return $this->Record['totalItems'];
} else {
return 0;
}
}
/*
* 新增取得分頁的方法
* 原本在phplib時是使用$db->query($sql);
* 查詢成功則會回傳true，失敗則回傳false
* 如果要分頁的話就利用
* 原本在phplib時是使用$db->Pager($sql);
* 查詢成功則會回傳分頁資訊，失敗則回傳false
*/
public function Pager($sql, $pager_options = [])
{
//因為無法使用可變變數取得$_開頭的超級全域變數，所以先利用參考的方式值到自定義的變
$post = &$_POST;
$get = &$_GET;
$request = &$_REQUEST;
//取得分頁變數的方式可為request、get、post
$method = (empty($pager_options['method'])) ? 'request' : $pager_options['method'];
$method = strtolower($method);
$method = $$method;
//取得分頁變數，例如pageVar為pageID，$method為post則分頁的變數則為$_POST['pageID']
$pageVar = (empty($pager_options['pageVar'])) ? 'pageID' : $pager_options['pageVar'];
//設定每頁幾筆
$pager_options['perPage'] = (empty($pager_options['perPage'])) ? 10 : $pager_options['perPage'];
//顯示同一個頁面顯示幾頁
$pager_options['delta'] = (empty($pager_options['delta'])) ? 10 : $pager_options['delta'];
//取得當前頁數
$pager_options['current'] = (empty($method[$pageVar])) ? 1 : $method[$pageVar];
//設定link的前置網址
$pager_options['link'] = (empty($pager_options['link'])) ? $_SERVER['PHP_SELF'] : $pager_options['link'];
//取得總筆數
$pager_options['totalItems'] = (empty($pager_options['totalItems'])) ? $this->getTotalItems($sql) : $pager_options['totalItems'];
$total = ceil($pager_options['totalItems'] / $pager_options['perPage']);
if ($pager_options['current'] < 1) {
$pager_options['current'] = 1;
} elseif ($pager_options['current'] > $total && $pager_options['current'] != 1) {
$pager_options['current'] = $total;
}
$pager_options['page_numbers'] = [
'current' => $pager_options['current'],
'total' => $total,
];
$pager_options['deltaStart'] = floor(($pager_options['page_numbers']['current'] - 1) / $pager_options['delta']) * $pager_options['delta'] + 1;
$pager_options['start'] = ($pager_options['current'] - 1) * $pager_options['perPage'];
$pager_options['offset'] = $pager_options['perPage'];
$pager_options['from'] = $pager_options['start'] + 1;
$pager_options['to'] = $pager_options['from'] + $pager_options['perPage'] - 1;
$limitSql = sprintf('%s LIMIT %s , %s', $sql, $pager_options['start'], $pager_options['offset']);
if ($this->query($limitSql)) {
return $pager_options;
} else {
return false;
}
}
}
//再次繼承
class DB extends MySQL
{
public $Host = 'localhost';
public $Database = 'test';
public $User = 'root';
public $Password = '';
}
```
使用方法
```php
$db = new DB;
$sql = 'SELECT * FROM account ORDER BY account';
$results = [];
$page = $db->Pager($sql, [
'perPage' => 10,
'delta' => 10,
'link' => 'index.php?op=default',
'pageVar' => 'page',
]);
if ($page) {
while ($db->next_record()) {
$results[] = $db->Record;
}
}
print_r($page);
print_r($result);
```
