源码目录在\vendor\laravel\framework\src\Illuminate\Database\Eloquent\Relations下
关系：一对多（One To Many）
场景：每篇博客都有若干条评论，每条评论只属于一篇博客
先定义两个Model，这里为了突出主要矛盾，删除了Model中部分无关代码
namespace App; use Illuminate\Database\Eloquent\Model; class Post extends Model
{
protected $table = 'posts';
public function Comments()
{
return $this->hasMany('App\Comment','PostID','CommentID');
}
}
以上是博客Post的模型，接下来是评论Comment的模型
namespace App; use Illuminate\Database\Eloquent\Model; class Comment extends Model
{
protected $table = 'comments';
public function Comment()
{
//
} public function Post()
{
return $this->belongsTo('App\Post','CommentID','PostID');
}
}
控制器里：
$articles=Post::where('id','>','50')->where('id','<','52')->get();
foreach($articles as $a){
//echo $a->id;
$comments=$a->Comments;
foreach($comments as $c){
//echo $c->id;
}
}