var test = function(id, company){
//public members
this.id = id;
this.company = company;
//private member
var age = 24;
//private method
var getAge = function(){
return this.age;
};
//public method
this.displayAge = function(){
console.log(getAge());
}
}
//invoking
var t = new test(1, 'XYZ Corp');
t.displayAge(); //undefined
Why is it not getting displayed
It's not being displayed because this.age is undefined. You want age.
Because of the scope of variables in js
A variable is visible inside a function not outside
var a = "foo"
function fooBar () {
var b = "bar"
console.log(a) // foo
console.log(b) // bar
}
console.log(a) // foo
console.log(b) // undefined
You want this:
var test = function(id, company){
//public members
this.id = id;
this.company = company;
//private member
var age = 24;
//private method
this.getAge = function(){
return age;
};
//public method
this.displayAge = function(){
console.log(this.getAge());
}
}
//invoking
var t = new test(1, 'XYZ Corp');
t.displayAge(); //undefined
Note that both "getAge" and "displayAge" need to be attached to this but your private variable "age" should not be.
this. Read stackoverflow.com/q/13418669/1048572