Laravel手动创建分页器

laravel自带的分页功能十分强大，只不过，在使用 groupBy 语句的分页操作时，无法由 Laravel 有效执行。如果你需要在一个分页结果集中使用groupBy，建议你查询数据库并手动创建分页器。(基于Laravel5.4，老版本可能需要修改个别地方)

默认分页功能示例代码如下：

<?php

namespace App\Http\Controllers;

use Illuminate\Support\Facades\DB;

use App\Http\Controllers\Controller;

class IndexControllerextends Controller

{

publicfunctionindex()

{

$person = DB::table('person')->paginate(15);

return view('index.pagTest',['person'=>$person]);

}

手动创建分页器，代码如下;

<?php

namespace App\Http\Controllers\Index;

use Illuminate\Http\Request;
use App\Http\Controllers\Controller;
use Illuminate\Support\Facades\DB;
use Illuminate\Pagination\LengthAwarePaginator;

class IndexController extends Controller
{
    //测试查询数据库并手动创建分页器
    public function paginationTest(Request $request){
        $perPage = 5;
        $page = $request->input("page",1)-1;
        $total = DB::table("person")
                    ->groupBy()
                    ->count();

        $items = DB::table("person")
                    ->groupBy()
                    ->skip($page*$perPage)
                    ->take($perPage)
                    ->get();

        $person = new LengthAwarePaginator($items, $total,$perPage);
        $person->withPath("pagTest");

        return view("index.paginationTest",['person' => $person]);
    }
}

讲解：理解LengthAwarePaginator构造函数的前三个参数，就能明白如何手动创建分页器

$person->withPath("pagTest")是设置baseUrl的方法

$item //手动查询到的数据

$total //所有符合条件的数据总数量

$perPage //每个页面，数据显示的条数

LengthAwarePaginator构造函数，代码如下

/**
* Create a new paginator instance.
*
* @param mixed $items
* @param int $total
* @param int $perPage
* @param int|null $currentPage
* @param array $options (path, query, fragment, pageName)
* @return void
*/
publicfunction __construct($items,$total,$perPage,$currentPage=null,array$options= [])
{
    foreach ($optionsas$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->pageName);
    $this->items=$itemsinstanceofCollection ?$items: Collection::make($items);
}

附上结果图(因为使用了路由，请忽略url的不同:)

Laravel手动创建分页器