MQTT使用起来也十分容易,基本上就那四五个函数:MQTTClient_create(创建客户端)、MQTTClient_connect(连接服务端)、MQTTClient_publishMessage(客户端->服务端发送消息)、MQTTClient_subscribe(客户端订阅某个主题)等等。其中,很多异步回调函数,需要自己去实现,如, MQTTAsync_setCallbacks(mqtt->_client, mqtt->_client...
// 解码函数位于mqtt_client_mqtt_publish_payload.dart 内///Converts an array of bytes to a character string.staticStringbytesToStringAsString(typed.Uint8Buffer message) {// 接收时采用Uint8finalsb =StringBuffer(); message.forEach(sb.writeCharCode);returnsb.toString(); } 通过对比可知,消息显示乱...
此函数还指定服务质量。 参数 含义 handle 指向MQTT客户端句柄的指针。句柄被成功从函数中返回的客户端引用所填充 topic 订阅的主题,可使用通配符。 qos 订阅的请求服务质量 DLLExportintMQTTClient_publishMessage ( MQTTClient handle,constchar*topicName, MQTTClient_message*msg, MQTTClient_deliveryToken*dt ) 作用...
QStringList subscribers = mqttServer.subscriptionsForTopic(message.topic().name()); for (const QString &clientId : subscribers) { QMqttClient *client = mqttServer.findClient(clientId); if (client && client->isConnected()) { client->publish(message.topic(), message.payload()); } } });...
printf("Failed to publish message, return code %d\n", rc); exit(EXIT_FAILURE); } printf("Waiting for up to %d seconds for publication of %s\n" "on topic %s for client with ClientID: %s\n", (int)(TIMEOUT/1000), PAYLOAD, TOPIC, CLIENTID); ...
MQTTClient_publishMessage(client, TOPIC, &pubmsg, &token); printf("Waiting for up to %d seconds for publication of %s\n" "on topic %s for client with ClientID: %s\n", (int)(TIMEOUT/1000), PAYLOAD, TOPIC, CLIENTID); rc = MQTTClient_waitForCompletion(client, token, TIMEOUT); ...
intmqtt_publish(mqtt_client_t* c,constchar* topic_filter,mqtt_message_t* msg) 向指定主题发布一个MQTT报文。参数只有mqtt_client_t 类型的指针,字符串类型的主题(支持通配符),要发布的消息(包括服务质量、消息主体)。 使用如下: mqtt_message_tmsg; ...
MQTT 是长连接,不建议每发一条消息就重新连接一次。然后 mqttClient.publish(topic, message) 是同步的还是异步的?如果是异步的,那你在发布 QoS 1 和 QoS 2 消息时,这个函数返回并不代表发布流程结束哦。在话题中显示帖子 首页 类别 常见问题解答/准则 服务条款 隐私政策 由Discourse 提供技术支持,启用 ...
public void publish(boolean retained, String topic, String pushMessage) { MqttMessage message = new MqttMessage(); message.setQos(mqttProperties.getQos()); message.setRetained(retained); message.setPayload(pushMessage.getBytes()); MqttDeliveryToken token; ...
client, "mqtt_publish", &msg); // MQTT Client 发布主题为 mqtt_publish 的消息给 MQTT Server...