HTML5 Canvas public var?

[Naphtali]

In HTML5 Canvas mode I am trying to access a child var inside an object similar to how I would in AS3 with public var. Any advice on this?

AS3

Parent object [root]

trace(childObj.age); // 10

Child object [childObj]

public var age:Number = 10;

JS

var childObject = this.childObj;
console.log(childObject.age); //undefined

Child object [childObj]

var age = 10;

[ClayUUID · Accepted solution]

To oversimplify a bit, child functions can read parent variables, but not the other way around. When a child function exits, its variables cease to exist (usually).

If you want to store data in an object that can be accessed externally, you have to assign it as a property instead.

this.age = 10;

[Naphtali]

Wonderful!

This was just the reply I was looking for. I don't suppose this is possible to make a child function trigger by using a 'once' or 'change' event on the property?

[ClayUUID]

Umm, is someone going to be changing property values without you knowing about it? I suppose if you really want to over-engineer things you could define a getter method that would then do whatever you want when a property value is changed.

https://javascriptplayground.com/es5-getters-setters/

Working with objects - JavaScript | MDN

[Naphtali]

So my project uses a bunch of child objects with varying values which need to be changed based on data which is downloaded from a database.

This data is then used for functions within the child object.

I am finding that the this.age property can be written but not read by the child object

Thanks for the resources I will look into them.