B4R Question How to convert this code to read Serial.readString();

void loop() { 

  if (Serial.available() > 0) {
    String incoming = Serial.readString();

    if (incoming.indexOf("{")>=0 && incoming.indexOf("}")>=0) { 
      Serial.flush(); 
      //saveData(incoming);
      //do something here
    }
 
    
  } 
 
}