enum

main.dart

void main() {
  printStatus(Status.Start);
}

enum Status{
  Start,
  OnGoing,
  Finish
}

void printStatus(Status status){
  switch(status){
    case Status.Start:
      print("starting . . . ");
      break;
    case Status.OnGoing:
      print("onGoing . . . ");
      break;
    case Status.Finish:
      print("finish . . . ");
      break;
  }
  
  if(status == Status.Start){
    print("starting . . . ");
  }else if(status == Status.OnGoing){
    print("onGoing . . . ");
  }else{
    print("finish . . . ");
  }
}