$re = '/name="__RequestVerificationToken" type="hidden"\s*value="(.+?)" /';
$str = '<input name="__RequestVerificationToken" type="hidden"
value="BeRYiSIRjZoQHq4VW8qbkgXlnnzdUINpFNoYF_ugx-FRk0tkImbQPhwyYjyz_0Q-w6F2A0gDOfMZrdklD6rVn6-QnYggfImb55f90V7nrD_kbSkT3-y3gPqoTFg0ynTBLyX5Lw2" />';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($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