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基于5.2版本
在开发过程中有这么一种情况,你请求Java api获取信息,由于信息较多,需要分页显示。Laravel官方提供了一个简单的方式paginate($perPage),但是这种方法只适用model、查询构建器。
今天说下 给定一个数组如何实现 和paginate方法一样的效果。
查看paginate方法源码
#vendor/laravel/framework/src/Illuminate/Database/Eloquent/Builder.php:480
public function paginate($perPage = null, $columns = ['*'], $pageName = 'page', $page = null)
{
$query = $this->toBase();
$total = $query->getCountForPagination();
$this->forPage(
$page = $page ?: Paginator::resolveCurrentPage($pageName),
$perPage = $perPage ?: $this->model->getPerPage()
);
return new LengthAwarePaginator($this->get($columns), $total, $perPage, $page, [
'path' => Paginator::resolveCurrentPath(),
'pageName' => $pageName,
]);
}
从上面就可以看出,分页的关键就在于LengthAwarePaginator。
LengthAwarePaginator的构造方法。
public function __construct($items, $total, $perPage, $currentPage = null, array $options = [])
{
foreach ($options as $key => $value) {
$this->{$key} = $value;
}
$this->total = $total;
$this->perPage = $perPage;
$this->lastPage = (int) ceil($total / $perPage);
$this->path = $this->path != '/' ? rtrim($this->path, '/') : $this->path;
$this->currentPage = $this->setCurrentPage($currentPage, $this->lastPage);
$this->items = $items instanceof Collection ? $items : Collection::make($items);
}
其实已经很明白了,假如要分页的数组为
[
['username'=>'zhangsan', 'age'=>26],
['username'=>'lisi', 'age'=>23],
['username'=>'wangwu', 'age'=>62],
['username'=>'zhaoliu', 'age'=>46],
['username'=>'wangmazi', 'age'=>25],
['username'=>'lanzi', 'age'=>24],
['username'=>'pangzi', 'age'=>21],
]
共7条数据,每页显示3条,共3页
use Illuminate\Pagination\LengthAwarePaginator;
use Illuminate\Pagination\Paginator;
use Illuminate\Http\Request;
# 仅做演示 #
function userList(Request $request) {
$users = [
['username'=>'zhangsan', 'age'=>26],
['username'=>'lisi', 'age'=>23],
['username'=>'wangwu', 'age'=>62],
['username'=>'zhaoliu', 'age'=>46],
['username'=>'wangmazi', 'age'=>25],
['username'=>'lanzi', 'age'=>24],
['username'=>'pangzi', 'age'=>21]
];
$perPage = 3;
if ($request->has('page')) {
$current_page = $request->input('page');
$current_page = $current_page <= 0 ? 1 :$current_page;
} else {
$current_page = 1;
}
$item = array_slice($users, ($current_page-1)*$perPage, $perPage); //注释1
$total = count($users);
$paginator =new LengthAwarePaginator($item, $total, $perPage, $currentPage, [
'path' => Paginator::resolveCurrentPath(), //注释2
'pageName' => 'page',
]);
$userlist = $paginator->toArray()['data'];
return view('userlist', compact('userlist', 'paginator'));
}
上面的代码中的重点是$item,如果不做注释1处理,得出的是所有7条数据。
注释2处就是设定个要分页的url地址。也可以手动通过 $paginator ->setPath(‘路径’) 设置。
页面中的分页连接也是同样的调用方式 {{ $paginator->render() }}
好了,基本就是这样,有纰漏的地方欢迎指正!