获得淘宝的_tb_token_

$cookiepath = 'cookie.txt';//cookie文件
if(file_exists($cookiepath)){
    $fp=fopen($cookiepath,"r");
    while(!(feof($fp)))
    {
        $text=fgets($fp);
        if(preg_match("/_tb_token_=(.*)(; v=0)/", $text, $matches)){
            $_tb_token_ = trim($matches[1]);
            break;
        }
    }
}