Is there a way to create an object property from within a method of the same object?

Question

Let's say I have an object life:

var life = {
    name: "John Doe",
    age: 45
};

And I call a method die 5 seconds after my webpage loads:

setTimeout(life.die, 5000);

var life = {
    name: "John Doe",
    age: 45,
    die: function() {
        //Die
    }   
};

How would I create a property dead from within the method die? Is it as simple as this?

die: function() {
    this.dead = true;
}

Or this?

die: function() {
    var this.dead = true;
}

Or do I need to use something else?

@Jai — It would touch `window.dead` not `life.dead` (unless strict mode was in play, in which case it would throw an exception). — Quentin, Sep 26 '18 at 10:09
You can't pass `life.die` to `setTimeout` **before** you define `life`! Please *test* your [mcve]s — Quentin, Sep 26 '18 at 10:10
But you're accessing `life.dead` within the object `life`, so shouldn't it be `this.dead`? I'm really confused also by the duplicate @Quentin provided, it kind of didn't answer my problem. — Jack Bashford, Sep 26 '18 at 10:20
@JBDouble05 — "But you're accessing life.dead within the object life" — No, you're accessing `this.dead` from a function which isn't associated with any object. Look at the duplicate question again. Pay special attention to the bit of the accepted answer headed "What you should know about this". — Quentin, Sep 26 '18 at 10:22

score 1 · Accepted Answer · answered Sep 26 '18 at 10:28

You can the use the variable name life and assign property dead internally in the function scope it will assign to the life object automatically. If you are using this means it will assign to window object.

     
    
     var life = {
            name: "John Doe",
            age: 45,
            die:  () => {
                life.dead = true;
                console.log(life)
            }
        };
        
        setTimeout(life.die, 5000);

Is there a way to create an object property from within a method of the same object?

1 Answers1