紧凑型 Laravel 中未定义的变量“注释”

Question

I am getting 'undefined offset 1' error. It does returns everything I need -> the posts and the comments in the category. However, I believe the 'Undefined Offset 1' problem is probably due to some post which have no replies to them?? -> thus, help.

I have 1. Category Model 2. Post Model 3. Comment Model

This is the show function in my Category Model

  public function show($id)
    {

        $category = Category::with('posts.comments')->find($id);


        return view('categories.show', compact('category'));
    }

I have made relation for 'Category hasMany Posts' -> 'Post hasMany Comments'.

Answer 1

You can try this

public function show($id)
{
    $comments = []; // Empty array to initialize the variable. This variable will be filled once the foreach statement is ran.
    $category = Category::find($id);
    if($category !== null) {
        $posts = $category->posts;

        foreach($posts as $post) {

            $comments = $post->comments;
        }

    }
    return view('categories.show', compact('posts', 'category', 'comments'));
}

Alternative method

public function show(Category $category) //same as... public function show($id)
{
    return view('categories.show', compact('category'));
    /*
    Render this content in the view.
    @foreach($category->posts as $post)
      {{-- Display Post Content --}}
      @foreach($post->comments as $comment)
        {{-- Display Comment Content --}}
      @endforeach
    @endforeach
    */
}

Answer 2

You are creating $comments variable inside foreach loop that make it's scope locally and will not be available outside foreach

To resolved this error you need to define your comments variable inside your function so that it is available in your function

public function show($id)
        {
            $comments = [];  // define it here
            $category = Category::find($id);
            if($category !== null) {
                $posts = $category->posts;

                foreach($posts as $post) {

                    $comments = $post->comments;
                }

            }

                return view('categories.show', compact('posts', 'category','comments'));
            }