$re = '/^["_A-Za-z0-9-\\\\+]+(\\\\.[_A-Za-z0-9-]+)*@(([^-][A-Za-z0-9-]+([A-Za-z0-9]+)*[.](ac|academy|accountants|ag|agency|airforce|am|as|army|asia|at|az|bargains|be|best|bike|biz|blue|bz|build|builders|business|buzz|boutique|cab|camera|careers|cc|cd|ch|cheap|click|club|cn|clothing|cool|co.at|co.gg|co.il|co.in|co.je|co.nz|co.tm|co.tt|co.uk|co.vi|co.za|codes|coffee|company|computer|construction|contractors|com|com.ag|com.az|com.cn|com.es|com.fr|com.gr|com.hr|com.ph|com.ro|com.tw|com.vn|cooking|country|cruises|de|dental|diamonds|diet|digital|directory|dk|domains|engineering|enterprises|email|equipment|es|estate|eu|exchange|farm|fi|fishing|flights|florist|fo|fr|gallery|gent|gg|gift|graphics|gs|guitars|guru|healthcare|help|hk|holdings|holiday|hosting|house|info|international|in|it|immo|io|je|jp|kg|kitchen|kiwi|koeln|land|li|lighting|limo|link|london|management|marketing|me|menu|mobi|ms|name|navy|net|net.ag|net.cn|net.nz|net.pl|net.ru|network|ninja|nl|no|nu|ooo|org|org.uk|ph|photo|photos|photography|pink|pizza|pl|plumbing|property|pt|recipes|red|rentals|restaurant|ro|rodeo|ru|se|sh|shoes|singles|solar|support|systems|tc|tattoo|tel|technology|tips|tm|to|today|top|tt|training|tv|us|vacations|ventures|vc|villas|vg|vodka|voyage|vu|ws|watch|wiki|zone))|([[][0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}[]])|([0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}))/';
$str = '1234567890@domain.comdsf';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php