无法在laravel集合上运行foreach循环，为foreach（）提供了无效参数

Question

我希望将一组Board对象传递到我的视图中。但是，它在刀片模板内的for循环失败。

这是视图的路径

Route::get('board', function () {
    $user = Auth::user();
    $board = Auth::user()->boards()->where('user_id', $user->id)->first();
    $boardColumns = $board->columns()->get();
    return view('pages.kanban', compact('user', 'board', 'boardColumns'));
});

这是dd方法的结果

Collection {#299 ▼
  #items: array:4 [▼
     0 => BoardColumn {#300 ▶}
     1 => BoardColumn {#301 ▶}
     2 => BoardColumn {#302 ▶}
     3 => BoardColumn {#303 ▶}

最后，这是针对每个循环的

        @foreach($boardColumns as $column)
            <li class="drag-column {{ $column->slug }}">
                <div class="drag-column-header">
                    <h2>{{ $column->name }}</h2>
                </div>
                <div class="drag-options" id="options{{ $loop->iteration }}"></div>
                <ul class="drag-inner-list" id="{{ $loop->iteration }}">
                    @foreach($column->tasks as $task)
                        <li class="drag-item"></li>
                    @endforeach
                </ul>

            </li>
        @endforeach