按给定顺序按索引值对数组进行排序 - Sorting an array by index value with given order

Sorting an array by index value with given order

也许标题没有多大意义，但我真正想要实现的是使用具有排序值的数组按其索引对数组进行排序：

$sortingValues = array(
    'category-1',
    'category-2',
    ...
    'category-9',
);
$categories['category-1'][] = $article;
$categories['category-2'][] = $article;
...
$categories['category-9'][] = $article;

我想要实现的是用$sortingValues中的排序值对$categories进行排序。

$sortingValues = array( 'category-1', 'category-4', 'category-2', 'category-9');
$categories = array( 'category-1' => 'cat1', 'category-2' =>'cat2', 'category-4' => 'cat4', 'category-9'=>'cat9');
//
foreach($sortingValues as $cat) {
  if(array_key_exists($cat, $categories)) {
   print $categories[$cat] . "'n"; 
  }
}

function cmp_sortingValues( $a, $b ) {
  global $sortingValues;
  if( $a == $b ) return 0;
  $apos = array_search( $a, $sortingValues );
  $bpos = array_search( $b, $sortingValues );
  return ( $apos>$bpos ) ? 1 : -1;
}
uksort( $categories, "cmp_sortingValues" );