PHP 数组函数 array_intersect_key()

<?php
   $input1 = array('black'  => 1, 'red'  => 2, 'green'  => 3 );
   $input2 = array('green' => 4, 'black' => 5, 'pink' => 6,);

   $result = array_intersect_key($input1, $input2);
   print_r($result);
?>