Dart enumerations,classes and objects

 Enumerations

Named list of related items

enum PersonProperties { firstName, lastName, age }

void test() {
  print(PersonProperties.firstName);
}

 

 Switch is the prefreed way of doing enumerations


 

Classes

class Person {
  void run() {
    print('Running');
  }

  void breathe() {
    print('Brething');
  }
}

void test() {
  //we have to first create instance of class to use it or we will get error
  final person = Person();
  person.run();
}

 Objects

final foo = Person();

Constructor

class Person {
  final String name;

  Person(this.name);
}

void test() {
  final foo = Person('him');
  print(foo.name);
}

Methods

class Person {
  final String name;

  Person(this.name);

  void printName() {
    print('I will now priny name of person');
    print(name);
  }
}

void test() {
  final foo = Person('him gogoi');
  foo.printName();
}

 Inheritance & Sub classing

 

class LivingThing {
  void breathe() {
    print('Liivng thing is breathing');
  }

  void move() {
    print('I am moving');
  }
}

class Cat extends LivingThing{}

void test() {
  final fluffers = Cat();
  fluffers.move();
  fluffers.breathe();
}

 Abstract Class

Abstract class can't be intitiated. Other classes can use its features but it can't initiate itself

Factory Constructor

 It is almost similar like prototype of Javascript

 

class Cat {
  final String name;
  Cat(this.name);

  factory Cat.fluffBall() {
    return Cat('Fluff Ball');
  }
}

void test() {
  final fluffers = Cat.fluffBall();
  print(fluffers.name);
}

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