在數組中循環以製作另一個數組php

Question

我有這個數組。最近幾個小時，我一直在嘗試循環，做出另一個將安排在各自主題的問題。

[23] => Array 
     (
      [right] => A list of station and network addresses with corresponding gateway IP address. 
      [id] => 23 
      [level] => Professional 
      [subject] => Array 
       (
        [0] => Array 
         (
         [tid] => 1 
        ) 

       [1] => Array 
        (
         [tid] => 6 
        ) 

      ) 

     [question] => What is an IP routing table? 
     [answer] => A list of host names and corresponding IP addresses. 
     [correct] => 0 
    ) 

[22] => Array 
    (
     [right] => Session hijacking attack 
     [id] => 22 
     [level] => Professional 
     [subject] => Array 
      (
       [0] => Array 
        (
         [tid] => 1 
        ) 

       [1] => Array 
        (
         [tid] => 6 
        ) 

      ) 

     [question] => How would an IP spoofing attack be best classified? 
     [answer] => Session hijacking attack 
     [correct] => 1 
    ) 

[21] => Array 
    (
     [right] => Repeater 
     [id] => 21 
     [level] => Intermediate 
     [subject] => Array 
      (
       [0] => Array 
        (
         [tid] => 1 
        ) 

       [1] => Array 
        (
         [tid] => 6 
        ) 

      ) 

我想製作下面的東西。

array ([tid1] => array (
          [0] array ( [question] => something) 
          [1] array ( [question] => somethingelse) 
          ) 
     [tid2] => array (
          [0] array ( [question] => something) 
          [1] array ( [question] => somethingelse) 
          ) 

但我無法做到這一點。做這個的最好方式是什麼？

Answer 1

假設你的數據是在一個數組稱爲$data並且因爲每一個問題可以有多個對象，每個問題可能會對最終陣列中出現多次：

$final = array(); 
foreach($data as $datum){ 
    $subjects = $datum['subject']; 
    foreach($subjects as $subject){ 
     $tid = 'tid' . $subject['tid']; 
     $final[$tid][] = array('question' => $datum['question']); 
    } 
}