将数组中的userid元​​素作为父键php

Question

我有一个数组，并且有一个userID键。我想要的是将userid作为父键。我当前的变量如下：

$data = array(
    [0]=>array(
        [userID] => 90
        [dateLogin] =>  23:35:13
        [type] => 28
    ), 

    [1]=>array(
        [userID] => 90
        [dateLogin] =>  23:35:10
        [type] => 29
    ), 
    [2]=>array(
        [userID] => 91
        [dateLogin] =>  23:35:13
        [type] => 25
    ), 

    [3]=>array(
        [userID] => 91
        [dateLogin] =>  23:35:10
        [type] => 23
    )
)

现在我想实现如下所示的输出，因为你可以看到用户ID，其中90和91成为键，并且里面有数组：

$data = array(
    [90]=> array(
        [0] => array(
            [userID] => 90
            [dateLogin] =>  23:35:13
            [type] => 28
         ),
        [1]=>array(
            [userID] => 90
            [dateLogin] =>  23:35:10
            [type] => 29
         ),
      ), 
      [91]=> array(
         [0]=>array(
            [userID] => 91
            [dateLogin] =>  23:35:13
            [type] => 25
          ),
        [1]=>array(
           [userID] => 91
           [dateLogin] =>  23:35:10
           [type] => 23
        )
     ), 
  )

到目前为止我所做的是：

   foreach ($data as $key => $value) {
       $data[$value['userID']] = array(); 
          foreach ($value as $k => $v) {
            if($v == $value['userID']){
                $data[$value['userID']][] = $value; 
            }
        }
    }

我现在可以将userID作为键，但其中的数组是错误的。我错了什么？请帮忙。感谢

Answer 1

不需要内部foreach，只需要一个就足够了：

$new_data = array();
foreach($data as $value) {
    $new_data[$value['userID']][] = $value;
           // ^ userID as key   ^ another dimension
}