如何在此 Laravel 应用程序中保留选定的下拉选项？

Question

我一直在 Laravel 8 中开发博客应用程序。

文章支持评论，评论需经过管理员审核后方可发表。

我添加了一个选择框来按状态过滤评论或仅显示全部评论：

<form class="d-flex align-items-center" method="get" action="{{ route('dashboard.comments')}}">
  <label for="commentsFilter" class="form-label mb-0 me-1">Filter</label>
  <select class="form-select" id="commentsFilter" name="filter" onchange="this.form.submit()">
     @foreach ($filters as $filter)
       <option value="{{ $filter->value }}" {{ $active_filter == $filter->value ? 'selected' : '' }}>{{ $filter->label }}</option>
    @endforeach
  </select>
</form>

刀片

在 CommentController 控制器中，我有：

class CommentController extends Controller
{

  public function index(Request $request)
  {
    // Total number of comments
    $comments_count =  Comment::count();

    // Total number of unapproved comments
    $unapproved_comments_count = Comment::where('approved', 0)->count();

    // Comments per page
    $per_page = 10;

    // Comments filters
    $filters = $filter = [
      (object)[
        'value' => 'all',
        'label' => 'All comments'
      ],
      (object)[
        'value' => 0,
        'label' => 'Unapproved'
      ],
      (object)[
        'value' => 1,
        'label' => 'Approved'
      ]
    ];

    // Get active filter from URL
    $active_filter = $request->query('filter');

    // Comments (with filter)
    $filter = $request->input('filter');

    $comments = Comment::orderBy('id', 'desc')
      ->when($filter !== 'all', function ($query) use ($filter) {
        return $query->where('approved', $filter);
      }, function ($query) {
        return $query->where('approved', 1)->orWhere('approved', 0);
      })
      ->paginate($per_page)->onEachSide(1);

    return view(
      'dashboard/article-comments',
        [
          'per_page' => $per_page,
          'current_page' => $comments->currentPage(),
          'comments' => $comments,
          'comments_count' => $comments_count,
          'unapproved_comments_count' => $unapproved_comments_count,
          'filters' => $filters,
          'active_filter' => $active_filter,
        ]
      );
  }
}

问题

当我选择查看所有评论（来自

<select>

元素）时，

<option value="all">All comments</option>

不会保持选中状态（而其他 2 个选项在选择时仍保持选中状态）。

问题

1. 当 URL 为

   dashboard/comments?filter=all

   时，如何保持“所有评论”选项处于选中状态？
2. 当 URL 为

   dashboard/comments

   时怎么办？

Answer 1

在选项标签中使用 if 语句，如下所示：

<option value="{{ $filter->value }}" @if($active_filter == $filter->value) selected @endif }}>{{ $filter->label }}</option>