Laravel5.5 手动分页和自定义分页样式的简单实现-巨人网络通讯

Laravel5.5 手动分页和自定义分页样式的简单实现

基于Laravel5.5 在项目实施过程中，需要对从接口中获取的数据（或者通过搜索工具查询出来的数据）进行分页

一、创建手动分页

在laravel自带的分页中，一般是通过数据库查询访问paginate()方法来达到分页的效果，like this：

class IndexControllerextends Controller

{  
  publicfunctionindex()
  {
    $person = DB::table('person')->paginate(15);
 
    return view('index.pagTest',['person'=> $person]);
  }
}

查看框架的分页源代码

#vender/laravel/framework/src/Illuminate/Database/Eloquent/Builder.php

/**
   * Paginate the given query.
   *
   * @param int $perPage
   * @param array $columns
   * @param string $pageName
   * @param int|null $page
   * @return \Illuminate\Contracts\Pagination\LengthAwarePaginator
   *
   * @throws \InvalidArgumentException
   */
  public function paginate($perPage = null, $columns = ['*'], $pageName = 'page', $page = null)
  {
    $page = $page ?: Paginator::resolveCurrentPage($pageName);
 
    $perPage = $perPage ?: $this->model->getPerPage();
 
    $results = ($total = $this->toBase()->getCountForPagination())
                  ? $this->forPage($page, $perPage)->get($columns)
                  : $this->model->newCollection();
 
    return $this->paginator($results, $total, $perPage, $page, [
      'path' => Paginator::resolveCurrentPath(),
      'pageName' => $pageName,
    ]);
  }

发现，分页用了 \Illuminate\Contracts\Pagination\LengthAwarePaginator 构造方法，查看这个构造方法

?php
 
namespace Illuminate\Pagination;
 
use Countable;
use ArrayAccess;
use JsonSerializable;
use IteratorAggregate;
use Illuminate\Support\Collection;
use Illuminate\Support\HtmlString;
use Illuminate\Contracts\Support\Jsonable;
use Illuminate\Contracts\Support\Arrayable;
use Illuminate\Contracts\Pagination\LengthAwarePaginator as LengthAwarePaginatorContract;
 
class LengthAwarePaginator extends AbstractPaginator implements Arrayable, ArrayAccess, Countable, IteratorAggregate, JsonSerializable, Jsonable, LengthAwarePaginatorContract
{
  /**
   * The total number of items before slicing.
   *
   * @var int
   */
  protected $total;
 
  /**
   * The last available page.
   *
   * @var int
   */
  protected $lastPage;
 
  /**
   * Create a new paginator instance.
   *
   * @param mixed $items
   * @param int $total
   * @param int $perPage
   * @param int|null $currentPage
   * @param array $options (path, query, fragment, pageName)
   * @return void
   */
  public function __construct($items, $total, $perPage, $currentPage = null, array $options = [])
  {
    foreach ($options as $key => $value) {
      $this->{$key} = $value;
    }
 
    $this->total = $total;
    $this->perPage = $perPage;
    $this->lastPage = max((int) ceil($total / $perPage), 1);
    $this->path = $this->path !== '/' ? rtrim($this->path, '/') : $this->path;
    $this->currentPage = $this->setCurrentPage($currentPage, $this->pageName);
    $this->items = $items instanceof Collection ? $items : Collection::make($items);
  }

如果要实现手动分页，只需要使用这个构造方法，给定参数，就能达到分页的效果

贴代码：

public function setPage2(Request $request,$data,$prepage,$total){

    #每页显示记录
    $prePage = $prepage;
    //$total =count($data);
    $allitem = $prepage *100;
    $total > $allitem ? $total = $allitem : $total;
    if(isset($request->page)){
      $current_page =intval($request->page);
      $current_page =$current_page=0?1:$current_page;
    }else{
      $current_page = 1;
    }
    #url操作
    $url = $url='http://'.$_SERVER['SERVER_NAME'].$_SERVER["REQUEST_URI"];
    if(strpos($url,'page')) $url=str_replace('page='.$request->page, '',$url);
 
    # $data must be array
    $item =array_slice($data,($current_page-1)*$prePage,$prePage);
    $paginator = new LengthAwarePaginator($item,$total,$prePage,$current_page,[
      'path'=>$url,
      'pageName'=>'page'
    ]);
 
    return $paginator;
  }

（$data 为需要进行分页的数据）

说明：

1、在考虑到代码的复用性，我将分页代码封装到app/Controllers/Controller.php中的一个方法里面，这样在其他控制器里只需要$this->setPage(Request $request,$data,$prepage,$total) 就能使用了，（前提：其他控制器继承了Controller.php）

2、分页的URL，因为我的项目的url一定会携带一个kw参数，所以我直接用str_replace替换"page",如果是存在不携参分页的话，需要判断，到底是"?page"还是"page"。（url的逻辑可以自己写）

#分页 php

     $paginator = $this->setPage2($request,$data,25,$sum);
      $data =$paginator->toArray()['data'];

在模板中：{{$paginator->render()}}即能输出分页HTML，样式如下：

二、自定义分页样式

在实际开发中，不希望用户在浏览时直接浏览最后几页，只想用户从前往后依次的浏览，如百度搜索分页，这时候，就想修改分页的样式，经过一个下午的奋战，贴出解决过程

在上一环节中，手动创建了分页，了解HTML的模板生成是render()方法，

#\Illuminate\Contracts\Pagination\LengthAwarePaginator


/**
   * Render the paginator using the given view.
   *
   * @param string|null $view
   * @param array $data
   * @return \Illuminate\Support\HtmlString
   */
  public function render($view = null, $data = [])
  {
    return new HtmlString(static::viewFactory()->make($view ?: static::$defaultView, array_merge($data, [
      'paginator' => $this,
      'elements' => $this->elements(),
    ]))->render());
  }

经过思考，我们不去改laravel框架的源代码，可以通过重构render方法或者重新定义一个生成HTML模板的方法来实现自定义HTML模板

因为我们只需要自定义HTML模板，所以，可以创建一个文件，继承\Illuminate\Contracts\Pagination\LengthAwarePaginator 类

看代码：

?php
 
namespace App\Helpers;
 
use Illuminate\Pagination\LengthAwarePaginator;
/**
 * Created by PhpStorm.
 * User: 1
 * Date: 2018/4/9
 * Time: 9:08
 */
class Newpage extends LengthAwarePaginator {
 
  public $de_page = 10; //默认显示分页数
  public $pageHtml;
 
  public function newrender(){
    if($this->hasPages())
    {
 
      return sprintf("ul class='pagination'>%s %s %s/ul>",
        $this->pre_page(),
        $this->pages_num(),
        $this->next_page()
      );
    }
  }
 
  #上一页
  public function pre_page(){
    if($this->currentPage == 1){
      //dd($this->currentPage);
      return "li class='disabled'>span>《/span>/li>";
    }else{
 
      $url = $this->path."page=".($this->currentPage-1);
      //dd($url);
      return "li>a href=".$url." rel="external nofollow" rel='prev'>《/a>/li>";
    }
  }
 
  #页码
  public function pages_num(){
    $pages = '';
    if($this->currentPage = 6){
      for($i = 1; $i = $this->de_page; $i++){
        if($this->currentPage == $i){
          $pages .= "li class='active'>a href=".$this->path." rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" page=".$i.">".$i."/a>/li>";
        }else{
          $pages .="li>a href=".$this->path." rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" page=".$i.">".$i."/a>/li>";
        }
      }
    }else{
      #当前页前边部分
      for($i = 5; $i >=1 ; $i--){
        $url =$this->currentPage-$i;
        $pages .= "li>a href=".$this->path." rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" page=".$url.">".$url."/a>/li>";
      }
      #当前页
      $pages .= "li class='active'>span>".$this->currentPage."/span>/li>";
      #当前页后边部分
      for($i = 1;$i  5; $i++ ){
        $nowpage =$this->currentPage+$i;
        $pages .= "li>a href=".$this->path." rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" page=".$nowpage.">".$nowpage."/a>/li>";
      }
    }
    return $pages;
 
  }
  #下一页
  public function next_page(){
    if($this->currentPage  $this->total){
      $page =$this->currentPage+1;
      return "li>a href=".$this->path." rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" page=".$page." rel='next'>span>》/span>/a>/li>";
    }else{
      return "li class='disabled'>span>》/span>/li>";
    }
 
  }
 
}

我选择的方法是自定义新的方法生成HTML模板，模板中通过：{{$paginator->newrender()}}输出HTML

如果选择重构render()方法，只需要将上面的newrender()方法做一些小变动

public function render($view=null,$data=[]){
 
    if($this->hasPages())
    {
      return sprintf("ul class='pagination'>%s %s %s/ul>",
        $this->pre_page(),
        $this->pages_num(),
        $this->next_page()
      );
    }
  }

模板中通过：{{$paginator->render()}}输出HTML

最终效果如图：