How to access object's constructor in Javascript?

Question

I have this piece of code:

var MyConstructor = function(){};
var MyObject = new MyConstructor();

What I noticed is MyObject.constructor is not pointing to MyConstructor. So what is the standard way of accessing the constructor of an object from the object itself?

I need this to access constructor's prototype properties like MyConstructor.prototype = {mykey : "value"}. I can access mykey this way: MyConstructor.prototype.mykey but MyObject.constructor.prototype.mykey is not defined.

Here is the complete code and their output using jsconsole.com:

var MyConstructor = function(){};
MyConstructor.prototype = {mykey : "value"};
var MyObject = new MyConstructor();

MyObject.mykey; // output: "value"
MyConstructor.prototype.mykey; // output: "value"
MyObject.constructor.prototype.mykey; // output: undefined
MyObject.constructor === MyConstructor; // output: false
MyObject.constructor.prototype.mykey === "value";  // output: false

Answer 1

Object.getPrototypeOf(MyObject).mykey gets the prototype directly from MyObject.

Mozilla developer link