微信公众平台开发者模式 关注后没有自动回复

Question

php后台实现微信公众平台的关注后自动回复功能，但是没有信息返回，代码如下
public function index(){
$request = Request::instance();
$get = $request->param();
$timestamp = $get['timestamp'];
$nonce = $get['nonce'];
$token = "weiwei";
$signature = $get['signature'];
$echostr = $get['echostr'];

$array = array();
$array = array($token,$timestamp,$nonce);
sort($array);
$tmpstr = sha1(implode('',$array));

if($tmpstr == $signature){
if (!isset($get['echostr'])) {
$this->responText();
}else{
ob_clean();
echo $get['echostr'];
exit;
}
}
}

private function responText(){
    $getInfo = $GLOBALS["HTTP_RAW_POST_DATA"];
    $InfoObj = simplexml_load_string($getInfo);

    if (strtolower(trim($InfoObj->MsgType))=='event') {
        if (strtolower($InfoObj->Event)=='subscribe') {

            $tousername = $InfoObj->FromUserName;
            $fromusername = $InfoObj->ToUserName;
            $ctime = time();
            $content = '欢迎关注本公众号,你果然是个聪明人';

            $Msg = "<xml>
                    <ToUserName><![CDATA[%s]]></ToUserName>
                    <FromUserName><![CDATA[%s]]></FromUserName>
                    <CreateTime>%s</CreateTime>
                    <MsgType><![CDATA[text]]></MsgType>
                    <Content><![CDATA[%s]]></Content>
                    </xml>";

            $sendMsg = sprintf($Msg,$tousername,$fromusername,$ctime,$content);
            echo $sendMsg;
        }
    }
}
    token是可以提交的，url上用的是阿里云服务器的ip地址，不是备案的域名，不知有没有影响，求大神指教！

Answer 1

http://blog.csdn.net/zhaokang491460192/article/details/17263341