Is it possible to tell if an variable is an object that was just created with new and get the object type?

Question

Is it possible to tell if an variable is an object that was just created with new and get the object type?

Let's take this code:

var charles = new Person();

Can I somehow inspect the charles variable and see that it was created with the new word and also find out that it is of type Person?

javascript
node.js
oop

Answer 1

You can use the instanceof operator:

var isPerson = charles instanceof Person

More info about it here

Answer 2

an instance is created by using new anyway unless a standard type like string or int etc.

so:

function exampleObj(){
    this.exampleAttr=1;
}

var exampleInstance = new exampleObj();

if(exampleInstance instanceof exampleObj){
    alert("i am an example");
}

The same applies for reserved types so instanceof String, instanceof int You always get a boolean.