过滤微信昵称名字中emoji

<?php
header("Content-Type:text/html;charset=utf-8");

$nike_name="💎miumiu糖～";
$nike_name=filter_emoji($nike_name);
echo $nike_name;
exit();


function filter_emoji($str) {  
    $regex = '/(\\\u[ed][0-9a-f]{3})/i';  
    $str = json_encode($str);  
    $str = preg_replace($regex, '', $str);  
    return json_decode($str);
}

?>