How to mimic constructor in JavaScript in OOP style?

Question

In an OOP way, I am defining a Person "class" as follows:

var Person = {

  name: '',

  age: 32,

  gender: 'male',

  interests: ['music', 'skiing'],

  bio: function() {

    alert(this.name[0] + ' ' + this.name[1] + ' is ' + this.age + ' years old. He likes ' + this.interests[0] + ' and ' + this.interests[1] + '.');

  },

  greeting: function() {

    alert('Hi! I\'m ' + this.name + '.');

  }

};

Now, I am instantiating the above class.

var person1= Object.create(Person);

person1.name = 'personname';

person1.greeting();

How can I mimic a constructor so that when Object.create(Person) creates a new object, the constructor code is automatically computed?

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Answer 1

You would wrap up the code in a function, and call it there. Object.create will establish a relationship with the prototype, but won't call any additional code automatically.

function person(name) {
  var person1 = Object.create(Person);
  person1.name = name;
  return person1;
}

person('personname').greeting();

You should also avoid uppercasing the first letter of variables unless they are functions which should be called using new. This is a naming convention used only for constructor functions.

How to mimic constructor in JavaScript in OOP style?

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