PHP Post::has方法代码示例

 /**
  * Execute the console command.
  *
  * @return mixed
  */
 public function handle()
 {
     $hashtag = $this->argument('hashtag');
     $GetterClass = '\\App\\Getters\\' . $this->argument('provider') . 'Getter';
     $TransformerClass = 'App\\Transformers\\' . $this->argument('provider') . 'Transformer';
     $getter = new $GetterClass();
     $this->info('Getting posts from ' . $this->argument('provider'));
     $posts = $getter->getList($this->argument('howmany'), $this->argument('hashtag'));
     // transform posts
     foreach ($posts as $key => $post) {
         $transformer = new $TransformerClass($post);
         $currentPost = $transformer->get();
         // store if it doesn't already exist
         if (!Post::has($currentPost['post_id'])) {
             // check if post is popular enough
             if ($this->argument('qualityThreshold')) {
                 if ($transformer->isPopular($this->argument('qualityThreshold'))) {
                     Post::create($currentPost);
                 }
             } else {
                 Post::create($currentPost);
             }
         }
     }
     // Cache last 50 posts
     $this->comment('Caching last fifty posts');
     $lastFiftyPosts = \App\Post::orderBy('date_published', 'DESC')->take(50)->get();
     Cache::put('lastFiftyPosts', $lastFiftyPosts, 5);
 }

 /**
  * Display a listing of the resource.
  *
  * @return \Illuminate\Http\Response
  */
 public function index()
 {
     $post_all = Post::latest()->published()->paginate(5);
     //get one to many
     $post = Post::find(11);
     if ($post) {
         $comments = $post->comments()->get();
     }
     //$comments->posts()->where('active', 1)->get();
     //$comments = Post::find(11)->comments()->where('title', 'foo')->first();
     //inverse
     $comment = Comment::find(1);
     if ($comment) {
         $post_found = $comment->post->title;
     }
     //many to many
     $user = User::find(32);
     if ($user) {
         $roles = $user->roles;
     }
     //$roles2 = User::find(11)->roles()->orderBy('role')->get();
     //Has Many Through
     $country = Country::find(1);
     $post_by_country = $country->posts;
     //Polymorphic
     //foreach ($post->likes as $like) {}
     //inverse
     $like = Like::find(1);
     if ($like) {
         $likeable = $like->likeable;
     }
     //Many To Many Polymorphic
     //$post = App\Post::find(1);
     //foreach ($post->tags as $tag) {}
     //inverse
     $tag = Tag::find(1);
     //Querying Relationship Existence
     // Retrieve all posts that have at least one comment...
     //$posts = Post::has('comments')->get();
     // Retrieve all posts that have three or more comments...
     $posts = Post::has('comments', '>=', 3)->get();
     // Retrieve all posts that have at least one comment with votes...
     //$posts = Post::has('comments.votes')->get();
     // Retrieve all posts with at least one comment containing words like foo%
     // $posts = Post::whereHas('comments', function ($query) {//orWhereHas
     //     $query->where('content', 'like', 'foo%');
     // })->get();
     //Eager loading
     $post2 = Post::with('user')->get();
     //Eager Loading Multiple Relationships
     //Sometimes you may need to eager load several different relationships in a single operation. To do so, just pass additional arguments to the with method:
     //$books = Post::with('user', 'publisher')->get();
     //Nested Eager Loading
     //To eager load nested relationships, you may use "dot" syntax. For example, let's eager load all of the book's authors and all of the author's personal contacts in one Eloquent statement:
     //$books = App\Book::with('author.contacts')->get();
     //Constraining Eager Loads
     //Sometimes you may wish to eager load a relationship, but also specify additional query constraints for the eager loading query. Here's an example:
     // $users = App\User::with(['posts' => function ($query) {
     //     $query->where('title', 'like', '%first%');
     // }])->get();
     //In this example, Eloquent will only eager load posts that if the post's title column contains the word first. Of course, you may call other query builder to further customize the eager loading operation:
     // $users = App\User::with(['posts' => function ($query) {
     //     $query->orderBy('created_at', 'desc');
     // }])->get();
     //Lazy Eager Loading
     //Sometimes you may need to eager load a relationship after the parent model has already been retrieved. For example, this may be useful if you need to dynamically decide whether to load related models:
     //$books = App\Book::all();
     // if ($someCondition) {
     //     $books->load('author', 'publisher');
     // }
     //If you need to set additional query constraints on the eager loading query, you may pass a Closure to the load method:
     // $books->load(['author' => function ($query) {
     //     $query->orderBy('published_date', 'asc');
     // }]);
     return view('posts.index', compact('post', 'comments', 'post_found', 'user', 'roles', 'roles2', 'country', 'post_by_country', 'likeable', 'tag', 'post2', 'post_all'));
 }