用两个数组替换值

Question

我从数据库中检索了这个数组：

Array $result['cities']
(
    [1] => New York, United States
    [2] => London, United Kingdom
)

这个关联数组：

Array $asso
(
    [United States] => us
    [United Kingdom] => gb
)

现在，我想将第一个数组转换为：

Array $newArray
(
    [1] => us
    [2] => gb
)

当然，它必须是动态的。我尝试使用这个但是一旦if条件成立，我就不知道如何选择匹配的密钥：

if (in_array('New York, United States', $result['cities'])) {
    /// So select the matched value and replace it with "us"...
}

if (in_array('London, United Kingdom', $result['cities'])) {
    /// So select the matched value and replace it with "gb"...
}

因此，正如您所理解的，我的问题可以翻译为：如何将数组A值替换为数组B的值，其中A值是B键？

Answer 1

试试这个 -

foreach($result['cities'] as $key => $cityInfo){
  list($city, $country) = explode(',', $cityInfo);
  if(isset($asso[$country])){
    $newArr[$key] = $asso[$country];
  }
}

Answer 2

$newArray = array_map(function ($e) use ($asso) {
    $countryName = trim(array_pop(explode(',', $e)));
    return $asso[$countryName];
}, $result['cities']);