Javascript calling other object method

Question

I have these two objects: A and B. I want to call A.something from B, but is not working...

A = function()
{
 function something()
 {
 //do something
 }
}
B = function()
{
 A.something();
}

this throws "typeError, A.something(); is not a function"...

Answer 1

Your current code attempts to use A as an object when it is a function. You would need to invoke the function A(), but then its something method would still not be available (because it is not exposed).

If you want A to be an object, you could use an object literal like this:

A = {
 something: function()
 {
 //do something
 }
}
B = function()
{
 A.something();
}

Or for a more classical looking approach you could use new:

function A()
{
 this.something()
 {
 //do something
 }
}
B = function()
{
 var a = new A();
 a.something();
}

There are more ways as well. You can use Object.create or use a more functional approach by returning an object inside the A function.

Answer 2

Don't declare A as a function itself, declare it as an object:

A = {}

Then inside place something as your function:

A = {
 something: function() {
 //do something
 }
}

You will now be able to call A.something().

Answer 3

First of all, to create an object in javascript you have to define your class A like this (easy approach, not using prototyping):

A = function()
{ 
 return {
 something = function()
 {
 //do something
 }
 }
}

Then create your object by calling var object = A().

So your code should look like this in the end:

A = function()
{ 
 return {
 something = function()
 {
 //do something
 }
 }
}
B = function()
{
 var aObject = A();
 aObject.something();
}

• Davin Tryon: How about the other ways to create an object? new or Object.create come to mind...
• RononDex: Well, that would be far to much to cover in this post. I will not write a tutorial on how to do object oriented coding in js
• Davin Tryon: I was referring to the you have to part of the first sentence.