php微信接收消息

     vaild();
    function (){
        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];
        $echostr = $_GET["echostr"];
        $token = TOKEN;
        $tmpArr = array($token, $timestamp, $nonce);
        sort($tmpArr, SORT_STRING);
        $tmpStr = implode( $tmpArr );
        $tmpStr = sha1( $tmpStr );
        if( $tmpStr == $signature && echostr){
            echo $echostr;
        }else{
            return false;
       }
    }
    responseMsg();
        function responseMsg(){
            $info = file_get_contents("php://input");
            $postObj = simplexml_load_string($info);
            $toUser     = $postObj->FromUserName;
            $fromUser  = $postObj->ToUserName;
            $time       = time();
            $msgType    = $postObj->MsgType;
            $content    = '你好啊';
            $template   = '<xml>
                            <ToUserName><![CDATA[%s]]></ToUserName>
                            <FromUserName><![CDATA[%s]]></FromUserName>
                            <CreateTime>%s</CreateTime>
                            <MsgType><![CDATA[%s]]></MsgType>
                            <Content><![CDATA[%s]]></Content>
                            </xml>';
            $response = sprintf($template,$toUser,$fromUser,$time,$msgType,$content);
            file_put_contents('./response.html', $response);
            echo $response;
        }