- var_dump: documentation ( source)
- array_intersect: documentation ( source)
- preg_replace: documentation ( source)
- key: documentation ( source)
<?php
$array1 = array(1=>"Band",2=>"Song", 3=>"Release",4=>"Year");
$array2 = array(1=>"Band");
$array1[key($array1)] = preg_replace("~^\xef\xbb\xbf~u","",$array1[key($array1)]);
var_dump(array_intersect($array1,$array2));