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JavaScript Object-Oriented JavaScript (2015) Constructor Functions and Prototypes Adding a Prototype

Pablo Grippo
Pablo Grippo
25,765 Points
Posted by Pablo Grippo
Pablo Grippo
25,765 Points

I can't figure out how the prototype is. Please, help me!

I'm trying to do the prototype method, but I can't. What's wrong? Thanks!

monster.js 
function Monster(name) {
  this.name = name;
  this.health = 100;
  Monster.prototype.takeDamage = function() {
    this.health--;
  }
}

1 Answer

Sam Roberton
Sam Roberton
7,225 Points
Sam Roberton
Sam Roberton
7,225 Points

As i understand it prototype is for use outside of an objects constructor, so you can have your function two ways.

function Monster(name) {
  this.name = name;
  this.health = 100;
}

Monster.prototype.takeDamage = function() {
    this.health--;
}

or

function Monster(name) {
  this.name = name;
  this.health = 100;
  this.takeDamage = function() {
    this.health--;
  }
}

Both can be called by using the same syntax.

var monster = new Monster("Henry");
monster.takeDamage();

Hope this helps :)