esp8266-ps-contrl/ESP32_socket/ESP32_socket.ino

#include <WiFi.h>

//网络配置
const char* ssid = "cdjs_work";
const char* password = "cdjs654321aA";

//sockt服务器地址
const char* host = "81.70.80.219";
const uint16_t port = 49700;
volatile uint16_t state = 0;
WiFiClient client;

// WIFI连接
void netConnect(){
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.println("WIFI connection...");
  }
  Serial.println("WiFi connected IP:");
  Serial.println(WiFi.localIP());    
}

//socekt 连接
void soConnect(){
  //  判断是否有网
  if(WiFi.status() == WL_CONNECTED){
    //若未连接到服务端，则客户端进行连接。
    if(client.connected()){
        //增加状态      
        if(state == 0){
          Serial.println("socket connected!");
          state = 1;
        }
        //  发送      
        delay(2000);
        Serial.println("发送：test");
        client.println("test");
    }else{
        //  判断状态
        if(state == 1){
          Serial.println("socket restart connection...");
          state = 0;
        }
        //  连接服务器
        Serial.println("socket connection..."); 
        client.connect(host, port);
        delay(1000);
    }
  }else{
    //  重新连接网络
    netConnect();
  }
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  netConnect();
}

void loop() {
  // put your main code here, to run repeatedly:
  soConnect();
}