微信应用开发之文本影子回复

【实例简介】微信应用开发接口文件，验证callback请求 签名是否正确

【核心代码】

class wechatCallbackapiTest
{
    public function valid()
    {
        $echoStr = $_GET["echostr"];
        if($this->checkSignature()){
            echo $echoStr;
            exit;
        }
    }

    private function checkSignature()
    {
        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];

        $token = TOKEN;
        $tmpArr = array($token, $timestamp, $nonce);
        sort($tmpArr);
        $tmpStr = implode( $tmpArr );
        $tmpStr = sha1( $tmpStr );

        if( $tmpStr == $signature ){
            return true;
        }else{
            return false;
        }
    }

    public function responseMsg()
    {
        $postStr = $GLOBALS["HTTP_RAW_POST_DATA"];
        if (!empty($postStr)){
            $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
            $RX_TYPE = trim($postObj->MsgType);

            //用户发送的消息类型判断
            switch ($RX_TYPE)
            {
                case "event":    //文本消息
                    $result = $this->receiveEvent($postObj);
                    break;
                case "text":    //文本消息
                    $result = $this->receiveText($postObj);
                    break;
                default:
                    $result = "unknow msg type: ".$RX_TYPE;
                    break;
            }
            echo $result;  //返回处理的结果
        }else {
            echo " ";
            exit;
        }
    }

    //接收文本消息
    private function receiveEvent($object)
    {
        $Event = $object->Event;
        if($Event =="subscribe"){
            $content = "欢迎关注";
        }else{
            $content = "你点击了菜单";
        }
        $result = $this->transmitText($object, $content);
        return $result;
    }
    private function receiveText($object)
    {
//        $content = "你发送的是文本，内容为：".$object->Content;
        $content = "2020";
        $result = $this->transmitText($object, $content);
        return $result;
    }

    //回复文本消息
    private function transmitText($object, $content)
    {
        $textTpl = "<xml>
                    <ToUserName><![CDATA[%s]]></ToUserName>
                    <FromUserName><![CDATA[%s]]></FromUserName>
                    <CreateTime>%s</CreateTime>
                    <MsgType><![CDATA[text]]></MsgType>
                    <Content><![CDATA[%s]]></Content>
                    </xml>";
        $result = sprintf($textTpl, $object->FromUserName, $object->ToUserName, time(), $content);
        return $result;
    }
}