$re = '/(^(post|merge|delete)\s(\/WcfDataService1\.svc\/)(.*)(HTTP\/1\.1)([\s]*)($|^{.*}))/im';
$str = '--batchitems
Content-Type: application/http
Content-Transfer-Encoding: binary
POST /WcfDataService1.svc/Orders(123) HTTP/1.1
{Order: 58}';
preg_match($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