在 Laravel 外使用 Eloquent（二）- 分页问题
2014-11-25
7 min read
上一篇《在Laravel外使用Eloquent（一）》 中我们演示了如何引入Eloquent以及基本使用，但是如果细心的朋友肯定会发现，当你在使用paginate(15)来分页的时候是会报错的。因为我们没有依赖laravel的pagination模块。但是引入那个模块同时它内部依赖了symfony的http-foundation模块，意味着为了一个分页功能我们要装好多东西。于是我就实现了一个比较简单的分页类：
代码见：https://github.com/overtrue/rester
<?php
namespace Rester;
/**
* Paginator.php
*
* (c) 2014 overtrue <anzhengchao@gmail.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*
* @author overtrue <anzhengchao@gmail.com>
* @github https://github.com/overtrue
* @url http://overtrue.me
* @date 2014-10-23T20:05:33
*/
use Closure;
use Countable;
use ArrayAccess;
use Serializable;
use ArrayIterator;
use JsonSerializable;
use IteratorAggregate;
class Paginator implements
ArrayAccess,
Countable,
IteratorAggregate,
Serializable,
JsonSerializable
{
protected $pager;
protected $pageSize;
protected $total;
protected $items;
/**
* Constructor
*
* @param \Slim\Http\Request $request
* @param string $pager
*/
public function __construct($pager = 'page')
{
$this->pager = $pager;
}
/**
* Make a pagination
*
* @param array $items
* @param integer $total
* @param integer $pageSize
*
* @return array
*/
public function make($items, $total, $pageSize = 10)
{
$this->total = abs($total);
$this->pageSize = $pageSize;
$this->items = $items;
return $this;
}
/**
* Return current page
*
* @return integer
*/
public function getCurrentPage($total = null)
{
$page = abs(app()->request->get('page', 1));
if ($total) {
$this->total = $total;
}
$page >= 1 || $page = 1;
if ($this->items) {
$totalPage = $this->getTotalPage();
$page <= $totalPage || $page = $totalPage;
}
return $page;
}
/**
* Return total pages
*
* @return integer
*/
public function getTotalPage()
{
$this->pageSize > 0 || $this->pageSize = 10;
$totalPage = ceil($this->total / $this->pageSize);
$totalPage >= 1 || $totalPage = 1;
return $totalPage;
}
public function links()
{
$html = '<ul class="pagination">';
$totalPage = $this->getTotalPage();
$currentPage = $this->getCurrentPage();
if ($totalPage < 10) {
for ($i = 1; $i <= $totalPage; $i++) {
$active = $i == $currentPage ? 'class="active"':'';
$html .= "<li $active><a href=".$this->getLink($i).">$i</a></li>";
}
} else {
if ($currentPage > 3) {
$html .= "<li><a href=".$this->getLink(1).">«</a></li>";
$start = $currentPage - 2;
} else {
$start = 1;
}
for ($i = $start; $i <= $currentPage; $i++) {
$active = $i == $currentPage ? 'class="active"':'';
$html .= "<li $active><a href=".$this->getLink($i).">$i</a></li>";
}
for ($i = $currentPage + 1; $i <= $currentPage + 3; $i++) {
$active = $i == $currentPage ? 'class="active"':'';
$html .= "<li $active><a href=".$this->getLink($i).">$i</a></li>";
}
if ($totalPage - $currentPage >= 5) {
$html .= "<li><a href='javascript:void(0)'>...</a></li>";
$html .= "<li><a href=".$this->getLink($totalPage).">$totalPage</a></li>";
}
}
return $html .= '</ul>';
}
/**
* getLink
*
* @param integer $page
*
* @return string
*/
public function getLink($page)
{
static $query;
if (is_null($query)) {
$query = app()->request->get();
}
$query['page'] = $page;
return "?" . http_build_query($query);
}
/** {@inhertDoc} */
public function jsonSerialize()
{
return $this->items;
}
/** {@inhertDoc} */
public function serialize()
{
return serialize($this->items);
}
/** {@inhertDoc} */
public function unserialize($data)
{
return $this->items = unserialize($data);
}
/** {@inhertDoc} **/
public function getIterator()
{
return new ArrayIterator($this->items);
}
/** {@inhertDoc} */
public function count($mode = COUNT_NORMAL)
{
return count($this->items, $mode);
}
/**
* Get a data by key
*
* @param string $key
*
* @return mixed
*/
public function __get($key) {
return $this[$key];
}
/**
* Assigns a value to the specified data
*
* @param string $key
* @param mixed $value
*
* @return void
*/
public function __set($key, $value)
{
$this->items[$key] = $value;
}
/**
* Whether or not an data exists by key
*
* @param string $key
*
* @return bool
*/
public function __isset($key)
{
return isset($this->items[$key]);
}
/**
* Unsets an data by key
*
* @param string $key
*/
public function __unset($key)
{
unset($this->items[$key]);
}
/**
* Assigns a value to the specified offset
*
* @param string $offset
* @param mixed $value
*
* @return void
*/
public function offsetSet($offset, $value)
{
$this->items[$offset] = $value;
}
/**
* Whether or not an offset exists
*
* @param string $offset
*
* @access public
*
* @return bool
*/
public function offsetExists($offset)
{
return isset($this->items[$offset]);
}
/**
* Unsets an offset
*
* @param string $offset
*
* @return array
*/
public function offsetUnset($offset)
{
if ($this->offsetExists($offset)) {
unset($this->items[$offset]);
}
}
/**
* Returns the value at specified offset
*
* @param string $offset
*
* @return mixed
*/
public function offsetGet($offset)
{
return $this->offsetExists($offset) ? array_get($this->items, $offset) : null;
}
}
然后在我们初始化eloquent的方装载这个分页类到eloquent中就好：
//...
use Rester\Paginator;
// 注册分页类
Capsule::setPaginator(function() use ($app, $config) {
return new Paginator($app->request, $config->get('pager', 'page'));
});
//...
完整的eloquent初始化步骤请参考：
https://github.com/overtrue/rester/blob/master/start/eloquent.php
然后我们就可以正常使用分页功能了：
$users = User::paginate(15);
$users = User::where('status', 1)->paginate(15);
...
因为上面的分页类实现了常用的预定义接口, 所以你可以很方便的使用分页结果：
// 遍历
foreach ($users as $user) {
// do sth.
}
// json encode
$json = json_encode($users);
// count
$count = count($users);
//...
另外还考虑到了大家不一定全用它写接口用，所以分页类同样实现了Laravel里的生成分页链接的方法：$users->links(), 它会生成bootstrap格式的分页列表：
<ul class="pagination">
<li><a href="#">«</a></li>
<li><a href="#">1</a></li>
<li><a href="#">2</a></li>
<li><a href="#">3</a></li>
<li><a href="#">4</a></li>
<li><a href="#">5</a></li>
<li><a href="#">»</a></li>
</ul>
demo:
<div class="container">
<?php foreach ($users as $user): ?>
<?php echo $user->name; ?>
<?php endforeach; ?>
</div>
<?php echo $users->links(); ?>
OK,那么现在你就可以很方便的在你的项目里无忧的使用Eloquent啦。