esp8266webserver get query params

#include 
ESP8266WebServer server(80); //creating the server at port 80

void setup() {
  Serial.begin(115200);
  server.on("/action1", action1);
  server.begin();
  pinMode(5, OUTPUT);
}

void action1() {
  String value = server.arg("value"); //this lets you access a query param (http://x.x.x.x/action1?value=1)
  int number = value.toInt();
  if(number == 0) {
    digitalWrite(5, LOW);
  } else {
    digitalWrite(5, HIGH);
  }
}

void loop() {
  server.handleClient();
}