Laravel5实现嵌套评论的形式（代码详解）

Schema::create('users', function (Blueprint $table) {
    $table->increments('id');
    $table->string('name');
    $table->string('email')->unique();
    $table->string('password');
    $table->rememberToken();
    $table->timestamps();
});

Schema::create('posts', function (Blueprint $table) {
    $table->increments('id');
    $table->string('title');
    $table->integer('user_id')->index();
    $table->text('content');
    $table->timestamps();
});

Schema::create('comments', function (Blueprint $table) {
    $table->increments('id');
    $table->integer('user_id')->index();
    $table->integer('post_id')->index();
    $table->integer('parent_id')->index()->default(0);
    $table->text('body');
    $table->timestamps();
});

/**
 * 一篇文章有多个评论
 * @return \Illuminate\Database\Eloquent\Relations\HasMany
 */
public function comments()
{
    return $this->hasMany(Comment::class);
}

/**
 * 获取这篇文章的评论以parent_id来分组
 * @return static
 */
public function getComments()
{
    return $this->comments()->with('owner')->get()->groupBy('parent_id');
}

/**
 * 这个评论的所属用户
 * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
 */
public function owner()
{
    return $this->belongsTo(User::class, 'user_id');
}

/**
 * 这个评论的子评论
 * @return \Illuminate\Database\Eloquent\Relations\HasMany
 */
public function replies()
{
    return $this->hasMany(Comment::class, 'parent_id');
}

\Auth::loginUsingId(1); //用户id为1的登录

//显示文章和相应的评论
Route::get('/post/show/{post}', function (\App\Post $post) {
    $post->load('comments.owner');
    $comments = $post->getComments();
    $comments['root'] = $comments[''];
    unset($comments['']);
    return view('posts.show', compact('post', 'comments'));
});

//用户进行评论
Route::post('post/{post}/comments', function (\App\Post $post) {
    $post->comments()->create([
        'body' => request('body'),
        'user_id' => \Auth::id(),
        'parent_id' => request('parent_id', null),
    ]);
    return back();
});

 - comments
comments.blade.php
form.blade.php
list.blade.php

 - posts
show.blade.php

nbsp;html>


    <meta>
    <meta>
    <meta>
    <link><div>
    <div>
        <h2>{{$post-&gt;title}}</h2>
        <h4>{{$post-&gt;content}}</h4>
        <hr>
        @include('comments.list',['collections'=&gt;$comments['root']])
        <h3>留下您的评论</h3>
        @include('comments.form',['parentId'=&gt;$post-&gt;id])
    </div>
</div>

<div>
    <h5>
<span>{{$comment-&gt;owner-&gt;name}}</span>:</h5>
    <h5>{{$comment-&gt;body}}</h5>

    @include('comments.form',['parentId'=&gt;$comment-&gt;id])

    @if(isset($comments[$comment-&gt;id]))
        @include('comments.list',['collections'=&gt;$comments[$comment-&gt;id]])
    @endif
    <hr>
</div>

@foreach($collections as $comment)
    @include('comments.comment',['comment'=>$comment])
@endforeach