我正在尝试创建一个博客,我有两个模型:Post 和 Tag。我想用数据透视表将它们连接起来。这是多对多的关系,我不知道如何将帖子和标签链接在一起。当我尝试这样做时,它不会在我的数据库上返回任何内容。帖子有标题和内容,而标签只有名称。 我读过我必须使用同步方法或附加分离,但我不知道在哪里执行此操作。是在帖子路线还是标签路线上?我已将帖子和标签的路由包含在 paths.php 中,并使用以下方法对它们进行分组:
Route::resource('/tags', 'TagController');
Route::resource('/posts', 'PostController');
这是我到目前为止所拥有的:
我的帖子模型:
class Post extends Model{
protected $fillable = [
'title', 'content'
];
protected $hidden = [
'view_count'
];
public function tags()
{
return $this->belongsToMany('App\Tag', 'post_tag');
}}
这是我的标签模型:
class Tag extends Model{
protected $fillable = [
'name'
];
public function posts(){
return $this->belongsToMany('App\Post', 'post_tag');
}}
这是我的 post_tag 数据透视表:
class CreatePostTagTable extends Migration{
public function up()
{
Schema::create('post_tag', function (Blueprint $table) {
$table->increments('id');
$table->integer('post_id')->unsigned()->nullable()->index();
$table->foreign('post_id')->references('id')->on('posts');
$table->integer('tag_id')->unsigned()->nullable()->index();
$table->foreign('tag_id')->references('id')->on('tags');
$table->timestamps();
});
}
public function down()
{
Schema::dropIfExists('post_tag');
}}
最佳答案
嘿,我也是 Laravel 的新手,我和你有同样的问题。对于您的情况,我认为最佳实践是将其附加到您的 PostController.php
中。让我把代码分享给你,希望对你有帮助
后 Controller
public function store (Request $request) {
// First we need to create variable that contain your tag_id
// $tags = [1, 2, 4]; something like this
$tags = $request->input('tags');
// Now storing the data in posts table
$post = new Post;
$post->title = $request->input('title');
$post->content = $request->input('content');
$post->save();
//After save the post, we need to attach it
$post->tags()->attach($tags);
}
编辑:添加示例 View
<div>
<input type="checkbox" id="subscribeNews" name="tags[]" value="1">
<label for="subscribeNews">Tag 1</label>
<input type="checkbox" id="subscribeNews" name="tags[]" value="2">
<label for="subscribeNews">Tag 2</label>
<input type="checkbox" id="subscribeNews" name="tags[]" value="3">
<label for="subscribeNews">Tag 3</label>
<input type="checkbox" id="subscribeNews" name="tags[]" value="n">
<label for="subscribeNews">More tag</label>
</div>
然后在PostController.php中,如果用户选中复选框,您可以获得id:
$tags = $request->input('tags');
编辑2:添加使用同步的示例
在这里,我给你举一个使用同步的小例子,首先让我们设置一个有 5 个标签的帖子。最后我们只想设置它3
$post = Post::find(1) //get the post with id 1, this post have 5 tags
// Let's say that this post have 5 tags with this ids [1, 2, 3, 4, 5]
// And then admin edit this post and select the tag with id [1, 2, 6] we set it in $tags variable
$tags = $request->input('tags'); //[1, 2, 6]
// And the last we just need to use sync method like this
$post->tags()->sync($tags);
// After use that, it will detach the tag based from removed ids [3, 4, 5] and attach new tag if there's new tag id [6]
// And in the end the post just have 3 tags
好吧,这就是示例逻辑,我也在学习它,但我希望它可以帮助你:D
关于laravel - 2 个带有数据透视表的模型,多对多关系,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/45234705/