'array']; public function participationError($userId): ?string { if ($this->end_time && strtotime($this->end_time) <= time()) return '当前问卷已截止'; if ($this->audience_course_ids && !CourseSign::where('user_id', $userId)->whereIn('course_id', $this->audience_course_ids)->where('status', 1)->exists()) return '您还未报名相关课程'; return null; } protected $appends = ['course_content']; public function getCourseContentAttribute() { if (empty($this->course_content_id)) { return []; } $course_content_id = explode(',', $this->course_content_id); return CourseContent::whereIn('id', $course_content_id)->get(); } public function course() { return $this->belongsTo(Course::class, 'course_id', 'id'); } public function courseContentEvaluationAsks() { return $this->hasMany(CourseContentEvaluationAsk::class, 'course_content_evaluation_id', 'id'); } public function courseContentEvaluationForms() { return $this->hasMany(CourseContentEvaluationForm::class, 'course_content_evaluation_id', 'id'); } }