二维数组中一维的一个 【键】作为二维【键的值】如何变换？

Question

这是初始数组：

$arr = array(
        'CC'=>array(
            'recharge_status'=> 1,
            'withdraw_status'=> 1,
            'trade_status'=> 1,
            'withdraw_fee'=> 0.01,
            'precision'=> 7,
        ),
        'DD'=>array(
            'recharge_status'=> 2,
            'withdraw_status'=> 2,
            'trade_status'=> 2,
            'withdraw_fee'=> 0.02,
            'precision'=> 8,
        ),
        'EE'=>array(
            'recharge_status'=> 3,
            'withdraw_status'=> 3,
            'trade_status'=> 3,
            'withdraw_fee'=> 0.03,
            'precision'=> 9,
        ),
    );

期望结果是：

$newarr = array(
        0=>array(
            'asset_code'=> 'CC',
            'recharge_status'=> 1,
            'withdraw_status'=> 1,
            'trade_status'=> 1,
            'withdraw_fee'=> 0.01,
            'precision'=> 7,
        ),
        1=>array(
            'asset_code'=> 'DD',
            'recharge_status'=> 2,
            'withdraw_status'=> 2,
            'trade_status'=> 2,
            'withdraw_fee'=> 0.02,
            'precision'=> 8,
        ),
        2=>array(
            'asset_code'=> 'EE',
            'recharge_status'=> 3,
            'withdraw_status'=> 3,
            'trade_status'=> 3,
            'withdraw_fee'=> 0.03,
            'precision'=> 9,
        ),
    );

Answer 1

$arr = array(
  'CC' => array(
    'recharge_status' => 1,
    'withdraw_status' => 1,
    'trade_status' => 1,
    'withdraw_fee' => 0.01,
    'precision' => 7,
  ),
  'DD' => array(
    'recharge_status' => 2,
    'withdraw_status' => 2,
    'trade_status' => 2,
    'withdraw_fee' => 0.02,
    'precision' => 8,
  ),
  'EE' => array(
    'recharge_status' => 3,
    'withdraw_status' => 3,
    'trade_status' => 3,
    'withdraw_fee' => 0.03,
    'precision' => 9,
  ),
);

$result = [];

foreach ($arr as $key => $value) {
  $value['asset_code'] = $key;
  $result[] = $value;
}

print_r($result);