Laravel 5 系列入门教程(四)【最适合中国人的 Laravel 教程】【完结】
本教程示例代码见:https://github.com/johnlui/Learn-Laravel-5
大家在任何地方卡住,最快捷的解决方式就是去看我的示例代码。
本文是本系列教程的完结篇,我们将一起给 Page 加入评论功能,让游客在前台页面可以查看、提交、回复评论,同时我们将在后台完善评论管理功能,可以删除、编辑评论。Page 和评论将使用 Eloquent 提供的“一对多关系”。最终,我们将得到一个个人博客系统的雏形,并布置一个大作业,供大家实战练习。
1. 初识 Eloquent
Laravel Eloquent ORM 是 Laravel 中非常重要的部分,也是 Laravel 能如此流行的原因之一。中文文档在:
1. http://laravel-china.org/docs/5.0/eloquent
2. http://www.golaravel.com/laravel/docs/5.0/eloquent/
在前面的教程中已经建立好的 learnlaravel5/app/Page.php 就是一个 Eloquent Model 类:
<?php namespace App; use Illuminate\Database\Eloquent\Model; class Page extends Model { // }
若想进一步了解 Eloquent,推荐阅读系列文章:深入理解 Laravel Eloquent
2. 创建 Comment 模型
首先我们要新建一张表来存储 Comment,命令行运行:
php artisan make:model Comment
成功以后,修改 migration 文件 learnlaravel5/database/migrations/***_create_comments_table.php 的相应位置为:
Schema::create('comments', function(Blueprint $table) { $table->increments('id'); $table->string('nickname'); $table->string('email')->nullable(); $table->string('website')->nullable(); $table->text('content')->nullable(); $table->integer('page_id'); $table->timestamps(); });
之后运行:
php artisan migrate
去数据库里瞧瞧,comments 表已经躺在那儿啦。
3. 建立“一对多关系”
修改 Page 模型:
<?php namespace App; use Illuminate\Database\Eloquent\Model; class Page extends Model { public function hasManyComments() { return $this->hasMany('App\Comment', 'page_id', 'id'); } }
搞定啦~ Eloquent 中模型间关系就是这么简单。
模型间关系中文文档:http://laravel-china.org/docs/5.0/eloquent#relationships
扩展阅读:深入理解 Laravel Eloquent(三)——模型间关系(关联)
4. 前台提交功能
修改 Comment 模型:
<?php namespace App; use Illuminate\Database\Eloquent\Model; class Comment extends Model { protected $fillable = ['nickname', 'email', 'website', 'content', 'page_id']; }
增加一行路由:
Route::post('comment/store', 'CommentsController@store');
运行以下命令创建 CommentsController 控制器:
php artisan make:controller CommentsController
修改 CommentsController:
<?php namespace App\Http\Controllers; use App\Http\Requests; use App\Http\Controllers\Controller; use Illuminate\Http\Request; use Redirect, Input; use App\Comment; class CommentsController extends Controller { public function store() { if (Comment::create(Input::all())) { return Redirect::back(); } else { return Redirect::back()->withInput()->withErrors('评论发表失败!'); } } }
修改视图 learnlaravel5/resources/views/pages/show.blade.php:
@extends('_layouts.default') @section('content') <h4> <a href="/">⬅️返回首页</a> </h4> <h1 style="text-align: center; margin-top: 50px;">{{ $page->title }}</h1> <hr> <div id="date" style="text-align: right;"> {{ $page->updated_at }} </div> <div id="content" style="padding: 50px;"> <p> {{ $page->body }} </p> </div> <div id="comments" style="margin-bottom: 100px;"> @if (count($errors) > 0) <div class="alert alert-danger"> <strong>Whoops!</strong> There were some problems with your input.<br><br> <ul> @foreach ($errors->all() as $error) <li>{{ $error }}</li> @endforeach </ul> </div> @endif <div id="new"> <form action="{{ URL('comment/store') }}" method="POST"> <input type="hidden" name="_token" value="{{ csrf_token() }}"> <input type="hidden" name="page_id" value="{{ $page->id }}"> <div class="form-group"> <label>Nickname</label> <input type="text" name="nickname" class="form-control" style="width: 300px;" required="required"> </div> <div class="form-group"> <label>Email address</label> <input type="email" name="email" class="form-control" style="width: 300px;"> </div> <div class="form-group"> <label>Home page</label> <input type="text" name="website" class="form-control" style="width: 300px;"> </div> <div class="form-group"> <label>Content</label> <textarea name="content" id="newFormContent" class="form-control" rows="10" required="required"></textarea> </div> <button type="submit" class="btn btn-lg btn-success col-lg-12">Submit</button> </form> </div> <script> function reply(a) { var nickname = a.parentNode.parentNode.firstChild.nextSibling.getAttribute('data'); var textArea = document.getElementById('newFormContent'); textArea.innerHTML = '@'+nickname+' '; } </script> <div class="conmments" style="margin-top: 100px;"> @foreach ($page->hasManyComments as $comment) <div class="one" style="border-top: solid 20px #efefef; padding: 5px 20px;"> <div class="nickname" data="{{ $comment->nickname }}"> @if ($comment->website) <a href="{{ $comment->website }}"> <h3>{{ $comment->nickname }}</h3> </a> @else <h3>{{ $comment->nickname }}</h3> @endif <h6>{{ $comment->created_at }}</h6> </div> <div class="content"> <p style="padding: 20px;"> {{ $comment->content }} </p> </div> <div class="reply" style="text-align: right; padding: 5px;"> <a href="#new" onclick="reply(this);">回复</a> </div> </div> @endforeach </div> </div> @endsection
前台评论功能完成。
查看效果:
5. 后台管理功能
修改基础视图 learnlaravel5/resources/views/app.blade.php 为:
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1"> <title>Laravel</title> <link href="/css/app.css" rel="stylesheet"> <!-- Fonts --> <link href='http://fonts.useso.com/css?family=Roboto:400,300' rel='stylesheet' type='text/css'> </head> <body> <nav class="navbar navbar-default"> <div class="container-fluid"> <div class="navbar-header"> <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1"> <span class="sr-only">Toggle Navigation</span> <span class="icon-bar"></span> <span class="icon-bar"></span> <span class="icon-bar"></span> </button> <a class="navbar-brand" href="#">Learn Laravel 5</a> </div> <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1"> <ul class="nav navbar-nav"> <li><a href="/admin">后台首页</a></li> </ul> <ul class="nav navbar-nav"> <li><a href="/admin/comments">管理评论</a></li> </ul> <ul class="nav navbar-nav navbar-right"> @if (Auth::guest()) <li><a href="/auth/login">Login</a></li> <li><a href="/auth/register">Register</a></li> @else <li class="dropdown"> <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">{{ Auth::user()->name }} <span class="caret"></span></a> <ul class="dropdown-menu" role="menu"> <li><a href="/auth/logout">Logout</a></li> </ul> </li> @endif </ul> </div> </div> </nav> @yield('content') <!-- Scripts --> <script src="//cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script> <script src="//cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.1/js/bootstrap.min.js"></script> </body> </html>
修改后台路由组(增加了一行):
Route::group(['prefix' => 'admin', 'namespace' => 'Admin', 'middleware' => 'auth'], function() { Route::get('/', 'AdminHomeController@index'); Route::resource('pages', 'PagesController'); Route::resource('comments', 'CommentsController'); });
创建 Admin\CommentsController :
php artisan make:controller Admin/CommentsController
Admin/CommentsController 要有 查看所有、查看单个、POST更改、删除四个接口:
<?php namespace App\Http\Controllers\Admin; use App\Http\Requests; use App\Http\Controllers\Controller; use Illuminate\Http\Request; use App\Comment; use Redirect, Input; class CommentsController extends Controller { public function index() { return view('admin.comments.index')->withComments(Comment::all()); } public function edit($id) { return view('admin.comments.edit')->withComment(Comment::find($id)); } public function update(Request $request, $id) { $this->validate($request, [ 'nickname' => 'required', 'content' => 'required', ]); if (Comment::where('id', $id)->update(Input::except(['_method', '_token']))) { return Redirect::to('admin/comments'); } else { return Redirect::back()->withInput()->withErrors('更新失败!'); } } public function destroy($id) { $comment = Comment::find($id); $comment->delete(); return Redirect::to('admin/comments'); } }
接下来创建两个视图:
learnlaravel5/resources/views/admin/comments/index.blade.php:
@extends('app') @section('content') <div class="container"> <div class="row"> <div class="col-md-10 col-md-offset-1"> <div class="panel panel-default"> <div class="panel-heading">管理评论</div> <div class="panel-body"> <table class="table table-striped"> <tr class="row"> <th class="col-lg-4">Content</th> <th class="col-lg-2">User</th> <th class="col-lg-4">Page</th> <th class="col-lg-1">编辑</th> <th class="col-lg-1">删除</th> </tr> @foreach ($comments as $comment) <tr class="row"> <td class="col-lg-6"> {{ $comment->content }} </td> <td class="col-lg-2"> @if ($comment->website) <a href="{{ $comment->website }}"> <h4>{{ $comment->nickname }}</h4> </a> @else <h3>{{ $comment->nickname }}</h3> @endif {{ $comment->email }} </td> <td class="col-lg-4"> <a href="{{ URL('pages/'.$comment->page_id) }}" target="_blank"> {{ App\Page::find($comment->page_id)->title }} </a> </td> <td class="col-lg-1"> <a href="{{ URL('admin/comments/'.$comment->id.'/edit') }}" class="btn btn-success">编辑</a> </td> <td class="col-lg-1"> <form action="{{ URL('admin/comments/'.$comment->id) }}" method="POST" style="display: inline;"> <input name="_method" type="hidden" value="DELETE"> <input type="hidden" name="_token" value="{{ csrf_token() }}"> <button type="submit" class="btn btn-danger">删除</button> </form> </td> </tr> @endforeach </table> </div> </div> </div> </div> </div> @endsection
learnlaravel5/resources/views/admin/comments/edit.blade.php:
@extends('app') @section('content') <div class="container"> <div class="row"> <div class="col-md-10 col-md-offset-1"> <div class="panel panel-default"> <div class="panel-heading">编辑评论</div> <div class="panel-body"> @if (count($errors) > 0) <div class="alert alert-danger"> <strong>Whoops!</strong> There were some problems with your input.<br><br> <ul> @foreach ($errors->all() as $error) <li>{{ $error }}</li> @endforeach </ul> </div> @endif <form action="{{ URL('admin/comments/'.$comment->id) }}" method="POST"> <input name="_method" type="hidden" value="PUT"> <input type="hidden" name="_token" value="{{ csrf_token() }}"> <input type="hidden" name="page_id" value="{{ $comment->page_id }}"> Nickname: <input type="text" name="nickname" class="form-control" required="required" value="{{ $comment->nickname }}"> <br> Email: <input type="text" name="email" class="form-control" required="required" value="{{ $comment->email }}"> <br> Website: <input type="text" name="website" class="form-control" required="required" value="{{ $comment->website }}"> <br> Content: <textarea name="content" rows="10" class="form-control" required="required">{{ $comment->content }}</textarea> <br> <button class="btn btn-lg btn-info">提交修改</button> </form> </div> </div> </div> </div> </div> @endsection
后台管理功能完成,查看效果:
6. 大作业
依赖于 Page 的评论功能已经全部完成,个人博客系统雏形诞生。在本系列教程的最后,布置一个大作业:构建出 Article 的前后台,并且加上 Article 与 Comment 的一对多关系,加入评论和评论管理功能。在做这个大作业的过程中,你将会反复地回头去看前面的教程,反复地阅读中文文档,会仔细阅读我的代码,等你完成大作业的时候,Laravel 5 就真正入门啦~~
教程(四)代码快照:https://github.com/johnlui/Learn-Laravel-5/archive/tutorial_4.zip
Laravel 5 系列入门教程【最适合中国人的 Laravel 教程】到此结束,谢谢大家!
评论:
2015-05-13 12:41
今天两个小时看完了博主四篇文章,不敢说都吃透了,最起码laravel的工作原理,前后台的关系算是理顺了。
只有一个问题想问一下博主,里面的那么多的函数等等都是从哪里查的?大多数应该是基于Eloquent吧,但是还有一些,例如Auth::guest()这种函数,我可能心里知道有这个需求,需要这么个函数,但是去哪里查找这个函数呢?
2015-04-30 20:04
Use of undefined constant App - assumed 'App' (View: /Users/vic/Sites/blog/resources/views/admin/comments/index.blade.php)
刚刚弄完还好好的,后来不知道改了哪里,在后台管理评论的列表页报这个错,没知道到底哪里出了问题,PO主希望给指点下。
2015-05-04 17:43
@section('content')
<div class="container">
<div class="row">
<div class="col-md-10 col-md-offset-1">
<div class="panel panel-default">
<div class="panel-heading">
<h3 class="panel-title">评论管理</h3>
</div>
<table class="table table-hover">
<thead>
<tr class="row">
<th>#</th>
<th>评论内容</th>
<th>发布人</th>
<th>邮箱</th>
<th>文章</th>
<th>Do</th>
</tr>
</thead>
<tbody>
@foreach ($comments as $comment)
<tr class="row">
<td>
{{ $comment->id }}
</td>
<td>
{{ $comment->content }}
</td>
<td>
@if ($comment->website)
<a target="_blank" href="{{ $comment->website }}">
{{ $comment->nickname }}
</a>
@else
{{ $comment->nickname }}
@endif
</td>
<td>
{{ $comment->email }}
</td>
<td>
<a href="{{ URL('pages/'.$comment->page_id) }}" target="_blank">
{{ App/Page::find($comment->page_id)->title }}
</a>
</td>
<td>
<form action="{{ URL('admin/comments/'.$comment->id) }}" method="POST" style="display: inline;">
<input name="_method" type="hidden" value="DELETE">
<input type="hidden" name="_token" value="{{ csrf_token() }}">
<div class="btn-group btn-group-xs" role="group" aria-label="Do">
<a href="{{ URL('admin/comments/'.$comment->id.'/edit') }}" class="btn btn-success">编辑</a>
<button type="submit" class="btn btn-danger">删除</button>
</div>
</form>
</td>
</tr>
@endforeach
</tbody>
</table>
</div>
</div>
</div>
</div>
@endsection
2015-05-04 18:45
改成:
{{ \App\Page::find($comment->page_id)->title }}
2015-04-21 17:54
QueryException in Connection.php line 620: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'admin/comments/1' in 'field list' (SQL: update `comments` set `page_id` = 1, `nickname` = fefe, `email` = fefe@qq.com, `website` = fefefe, `content` = feffffeeeeeeeeefeeeeeeeeeeeeeeeeeeeeeee, `admin/comments/1` = , `updated_at` = 2015-04-21 09:40:17 where `id` = 1)
2015-05-14 11:14

public function update(Request $request, $id)
{
$this->validate($request, [
'nickname' => 'required',
'content' => 'required',
]);
if (Comment::where('id', $id)->update(Input::except(['_method', '_token', 's']))) {
return Redirect::to('admin/comments');
} else {
return Redirect::back()->withInput()->withErrors('更新失败!');
}
}
是会出现这种情况,我打印出来的时候有个 ['s'] => 'admin/comments/1',我在这里过滤了s后解决的,我想知道的是laravel提交的时候,是会将action的参数以s命名传递给后台还是代码那里出现了问题
2015-04-14 23:27
2015-04-13 17:57
ReflectionException in compiled.php line 1029:
Class App\Http\Controllers\Admin\AdminHomeComtroller does not exist
2015-04-05 11:56
2015-03-28 17:39
2015-03-27 10:40
我在点击提交修改和删除按钮之后总是出现MethodNotAllowedHttpException in compiled.php line 7717:错误是怎么回事呢?
2015-03-18 23:38
如何理解以及正确的使用service provider? 为什么要使用service provider?
根据我的理解service provider 的概念是向Ioc容器注册特定的服务,当需要某个服务的时候可以直接从Ioc容器中获取服务实例使用。
比起使用命名空间,service provider 的优势是什么?
是依赖注入么?根据自己在laravel 5上的实验,使用use app/Repositories 这种命名空间方式,laravel 5同样可以实现对于方法的依赖注入。
想到一点优势是服务代理与服务实例分离,当想要替换服务实现的时候,可以简单的通过ServiceProvider 进行修改,而不用像命名空间一样每个文件一一替换。
还有可以依据参数动态绑定服务实现。
除了以上两点以外,service provider 还有哪些优势?应该在什么样的需求下使用service provider?
3ks
2015-03-12 15:28
Route::post('auth/register', 'Auth\AuthController@postregister');
我配了2个这样的路由没问题了,但是注册成功后 他是跳转到 http://127.0.0.1/home
这个控制器的跳转不知道在什么地方改下
2015-05-14 11:03
关于article的comment,我想用一个comment表来管理page和article中的所有comment。我在comment表中添加了一栏叫article_id.
目前的状态是,当添加page的comment,一切正常,article_id会自动赋给0;
当添加article的comment的时候有问题,我前台添加评论代码如下,但是添加的comment的page_id和article_id都是0;但我在前台调试过,确定name='article_id'栏的value确实取到了article的id,但是就是没有存进数据库。
<div id="new">
<form action="{{ URL('comment/store') }}" method="POST">
<input type="hidden" name="_token" value="{{ csrf_token() }}">
<input type="hidden" name="article_id" value="{{ $article->id }}">
<div class="form-group">
<label>Nickname</label>
<input type="text" name="nickname" class="form-control" style="width: 300px;" required="required">
</div>
<div class="form-group">
<label>Email address</label>
<input type="email" name="email" class="form-control" style="width: 300px;">
</div>
<div class="form-group">
<label>Home article</label>
<input type="text" name="website" class="form-control" style="width: 300px;">
</div>
<div class="form-group">
<label>Content</label>
<textarea name="content" id="newFormContent" class="form-control" rows="10" required="required"></textarea>
</div>
<button type="submit" class="btn btn-lg btn-success col-lg-12">Submit</button>
</form>
</div>