如何數組具有相同索引

Question

結合我有一個數組如下

[{"2":[2]},{"9":[4,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27,28,30,32,33,34,36,41]},{"2":[5,6,9]},{"7":[7,8]},{"9":[3]}] 

是那裏的值相同的索引合併任何可能的方式？

Answer 1

是的，這是可能的解碼JSON字符串並且使用array_reduce：

$arr = json_decode('[{"2":[2]},{"9":[4,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27,28,30,32,33,34,36,41]},{"2":[5,6,9]},{"7":[7,8]},{"9":[3]}]'); 

$arr = array_reduce($arr, function ($carry, $item) { 
    $key = key($item); 

    if (isset($carry[$key])) { 
     $carry[$key]->$key = array_merge($carry[$key]->$key, $item->$key); 
    } else { 
     $carry[$key] = $item; 
    } 

    return $carry; 
}); 

echo json_encode(array_values($arr)); 

結果是：

[{ 「2」：[2,5,6,9]} ，{ 「9」：[4,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27,28,30,32,33 ，34,36,41,3]}，{ 「7」：[7,8]}]

Answer 2

<?php 
$json = '[{"2":[2]},{"9":[4,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27,28,30,32,33,34,36,41]},{"2":[5,6,9]},{"7":[7,8]},{"9":[3]}]'; 
$multi_array = json_decode($json, true); 
$result = []; 
foreach($multi_array as $arr) 
{   
    foreach($arr as $k => $v) 
    { 
     $temp = isset($result[$k]) ? $result[$k] : []; 
     $result[$k] = array_merge($temp, $v); 
    } 
} 
print_r($result); 

Answer 3

這是另一種選項：

$old = json_decode('[{"2":[2]},{"9":[4,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27,28,30,32,33,34,36,41]},{"2":[5,6,9]},{"7":[7,8]},{"9":[3]}]', true); 

$new = []; 
array_map(function ($arr) use (&$new) { 
    $key = key($arr); 

    $new[$key] = array_merge(current($arr), !empty($new[$key]) ? $new[$key] : []); 
}, $old); 

echo json_encode($new); 

輸出：

{"2":[5,6,9,2],"9":[3,4,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27,28,30,32,33,34,36,41],"7":[7,8]}