实践

  1. function Animal(){
  2.   this.name = 'animal';
  3. }
  5. Animal.prototype.say=function(){
  6.   console.log('my name is ' + this.name);
  7. }
  9. function Bird(name,weight){
  10.   this.weight = weight;
  11.   return this;
  12. }
  14. Bird.prototype.fly = function(){
  15.   console.log('I am a Bird, I can fly');
  16. }
  18. // Bird.prototype = new Animal();
  19. // 等价
  20. Bird.prototype.__proto__ = Animal.prototype;
  21. Animal.call(Bird.prototype);
  23. console.dir(Bird);
  24. var bird = new Bird('bird',123);
  25. console.dir(bird);
  26. bird.say()
  29. var obj = {};
  30. console.dir(obj);