通过内部数组键和值获取外部数组键答案

【问题标题】：GET OUTER ARRAY KEY BY INNER ARRAY KEY AND VALUE通过内部数组键和值获取外部数组键
【发布时间】：2015-12-16 11:12:52
【问题描述】：

5 Array 

( 
  [0] => stdClass Object ( [question_id] => 1 [question_id_count] => 3 ) 
  [1] => stdClass Object ( [question_id] => 2 [question_id_count] => 3 ) 
  [2] => stdClass Object ( [question_id] => 3 [question_id_count] => 3 ) 
  [3] => stdClass Object ( [question_id] => 4 [question_id_count] => 5 ) 
  [4] => stdClass Object ( [question_id] => 5 [question_id_count] => 3 ) 
)

这里我需要输出 3 ,key - question_id_count 的值为 3

【问题讨论】：

标签： php multidimensional-array key

【解决方案1】：

您可以迭代数组，如果当前对象属性匹配，则保存键：

$outerKey = null;
foreach($array as $key => $value){
    if($value->question_id == 3){
        $outerKey = $key;
        break;
    }
}
var_dump($outerKey); //int(2)

【讨论】：