ESP8266连接阿里云实现点灯代码

很高兴为您解答。以下是ESP8266连接阿里云实现点灯代码的示例：

#include <ESP8266WiFi.h>
#include <PubSubClient.h>

const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";
const char* mqttServer = "your_mqtt_server";
const int mqttPort = 1883;
const char* mqttUser = "your_mqtt_user";
const char* mqttPassword = "your_mqtt_password";

const char* topic = "your_topic";
const char* clientId = "ESP8266Client";
const char* deviceCode = "your_device_code";
const char* productKey = "your_product_key";

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
  client.setServer(mqttServer, mqttPort);
  client.setCallback(callback);
  while (!client.connected()) {
    if (client.connect(clientId, mqttUser, mqttPassword)) {
      Serial.println("Connected to MQTT server");
      client.subscribe(topic);
    } else {
      Serial.print("Failed to connect to MQTT server, rc=");
      Serial.print(client.state());
      Serial.println(" retrying in 5 seconds");
      delay(5000);
    }
  }
}

void loop() {
  client.loop();
}

void callback(String topic, byte* message, unsigned int length) {
  Serial.print("Message received on topic: ");
  Serial.print(topic);
  Serial.print(". Message: ");
  String messageTemp;
  for (int i = 0; i < length; i++) {
    messageTemp += (char)message[i];
  }
  Serial.println(messageTemp);
  if (messageTemp == "ON") {
    digitalWrite(LED_BUILTIN, HIGH);
    String params = String("params={\"LightSwitch\":") + String(1) + "}";
    String requestStr = String("thing.event.property.post");
    String payload = String("{\"id\":\"123456\",\"version\":\"1.0\",\"method\":\"thing.event.property.post\",\"params\":{}}");
    requestStr += "\n" + deviceCode + "\n" + productKey + "\n" + requestStr + "\n" + params;
    Serial.println(requestStr);
    client.publish(topic, requestStr.c_str());
  } else if (messageTemp == "OFF") {
    digitalWrite(LED_BUILTIN, LOW);
    String params = String("params={\"LightSwitch\":") + String(0) + "}";
    String requestStr = String("thing.event.property.post");
    String payload = String("{\"id\":\"123456\",\"version\":\"1.0\",\"method\":\"thing.event.property.post\",\"params\":{}}");
    requestStr += "\n" + deviceCode + "\n" + productKey + "\n" + requestStr + "\n" + params;
    Serial.println(requestStr);
    client.publish(topic, requestStr.c_str());
  }
}

需要替换的部分：
- your_SSID: 你的WiFi名称
- your_PASSWORD: 你的WiFi密码
- your_mqtt_server: MQTT服务器地址
- your_mqtt_user: MQTT用户名
- your_mqtt_password: MQTT密码
- your_topic: MQTT订阅/发布的主题
- your_device_code: 设备的设备编码
- your_product_key: 产品的产品Key

需要注意的是，该代码还需要在你的Aliyun IoT平台的物模型属性里定义一个LightSwitch属性，用于控制LED灯的开关。

我希望我的回答能对你有帮助。