雄辩的关系 - 附加(但不保存)到 Has Many [英] Eloquent relations - attach (but don't save) to Has Many

问题描述

我建立了以下关系:

类页面{公共功能评论(){return $this->hasMany('Comment');}}类评论{公共功能页面(){return $this->belongsTo('Page');}}

非常标准.一页可以有多条评论，一条评论属于一页.

我希望能够创建一个新页面:

$page = 新页面；

还有评论

$comment = 新评论；

并将评论附加到页面，不保存任何内容

$page->comments->associate($comment);

我尝试了以下方法:

//这些是来自 MANY 方面的一对多(例如 $comment->page->associate...)$page->comments->associate($comment);//调用未定义的方法 IlluminateDatabaseEloquentCollection::associate()$page->comments()->associate($comment);//调用未定义的方法 IlluminateDatabaseQueryBuilder::associate()//这2个是多对多关系，所以不工作$page->comments->attach($comment);//调用未定义的方法 IlluminateDatabaseEloquentCollection::attach()$page->comments()->attach($comment);//调用未定义的方法 IlluminateDatabaseQueryBuilder::attach()//这 2 个将(如果成功)保存到我不想要的数据库中$page->comments->save($comment);//调用未定义的方法 IlluminateDatabaseEloquentCollection::save()$page->comments()->save($comment);//完整性约束违规:1048 列 'page_id' 不能为空

真正奇怪的是，做相反的事情(将页面附加到评论)可以正常工作:

$comment->page()->associate($page);

相关文档在 here 但他们没有提到附加到 ONE 方面一对多的.甚至可能吗?(我觉得应该是)

解决方案

听起来您只是想将新的评论对象添加到页面的评论集合中 - 您可以使用基本的集合添加方法轻松地做到这一点:

p>

$page = 新页面；$comment = 新评论；$page->comments->add($comment);

I have the following relations set up:

class Page {
    public function comments() {
        return $this->hasMany('Comment');
    }
}

class Comment {
    public function page() {
        return $this->belongsTo('Page');
    }
}

Pretty bog standard. One page can have many comments, and one comment belongs to a single page.

I'd like to be able to create a new page:

$page = new Page;

and a comment

$comment = new Comment;

and attach the comment to the page, without saving any of it

$page->comments->associate($comment);

I've tried the following:

// These are for one-to-many from the MANY side (eg. $comment->page->associate...)
$page->comments->associate($comment);   // Call to undefined method IlluminateDatabaseEloquentCollection::associate()
$page->comments()->associate($comment); // Call to undefined method IlluminateDatabaseQueryBuilder::associate()

// These 2 are for many-to-many relations, so don't work
$page->comments->attach($comment);      // Call to undefined method IlluminateDatabaseEloquentCollection::attach()
$page->comments()->attach($comment);    // Call to undefined method IlluminateDatabaseQueryBuilder::attach()

// These 2 will (if successful) save to the DB, which I don't want
$page->comments->save($comment);        // Call to undefined method IlluminateDatabaseEloquentCollection::save()
$page->comments()->save($comment);      // Integrity constraint violation: 1048 Column 'page_id' cannot be null

The really odd thing is that doing the opposite (attaching the page to the comment) works correctly:

$comment->page()->associate($page);

The relevant docs are here but they don't make any mention of attaching to the ONE side of a one-to-many. Is it even possible? (I feel like it should be)

解决方案

It sounds like you just want to add the new comment object to the page's comments collection - you can do that easily, using the basic colection add method:

$page = new Page;
$comment = new Comment;
$page->comments->add($comment);

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