foreach 仅返回 1 个值 Laravel

Question

我想展示一个包含问题和答案的测试。一个问题有4个答案。但我只得到了所有问题的 4 个答案。我该如何解决它？

   public function xem($id){
    $quests_of_test = QuestofTest::where('id_test', $id)->get();
  
    $ids = $quests_of_test->pluck('id_quest')->all();

    $questions = Question::whereIn('id', $ids)->get();

    foreach($questions as $quest){
        $answers = Answer::where('id_quest', $quest->id)->get();
    }
    
   
    return view('Test::xem', compact('questions', 'answers'));
}

Answer 1

就这样做吧

public function xem($id){

$quests_of_test_ids = QuestofTest::where('id_test', $id)->pluck('id_quest')->toArray();
$questions = Question::query()->whereIn('id', $quests_of_test_ids)->with('answers')->get();

return view('Test::xem', compact('questions'));
}

在视图中，当你迭代$question时，你可以做$question->answer

但在此之前你应该这样做

public function answer()
{
     return $this->hasOne(Answer::class, 'id_which_by_related')
     //return $this->hasMany(Answer::class, 'id_which_by_related') in case it has many answers so u should foreach it to iterate collection of answers
}

因为 foreach 中的变量被下一次迭代覆盖，所以你得到了上一次迭代数据

处理你的代码，不要再这样做了，请了解连接和关系

Answer 2

原因是变量

$answers

将为foreach内的每个循环重新分配。

您可以使用

$answers = [];
foreach($questions as $quest){
    $answers = array_merge($answers, Answer::where('id_quest', $quest->id)->get());
}

Answer 3

如果您正确定义了您的关系，您可以使用 Eager Loading 来获取问题的所有答案。

public function xem($id) {
    $quests_of_test = QuestofTest::where('id_test', $id)->get();
  
    $ids = $quests_of_test->pluck('id_quest')->all();

    $questions = Question::with('answers')->whereIn('id', $ids)->get();
   
    return view('Test::xem', compact('questions'));
}