如何用php抓取網頁中郵箱地址代碼

<?php
    /*
    desc：采集網頁中的郵箱的代碼
    /
    $url='contents($url);
    //echo $content;
    function getEmail($str) {
    //$pattern = "/([a-z0-9]*[-.]?[a-z0-9]+)@([a-z0-9][-]?[a-z0-9]+)+[.][a-z]{2,3}([.][a-z]{2})?/i";
    $pattern = "/([a-z0-9-.]+@[a-z0-9]+.[a-z0-9-_.]+)/";
    preg_match_all($pattern,$str,$emailArr);


return $emailArr[0];
}
print_r( getEmail($content));
?></pre>