How do I get to a certain place in my JavaScript object using variables?

Question

I have a JavaScript object called 'winners' that looks like this:

var winners = {
    rock: {
        "scissors": true,
        "paper": false
    }
    paper: {
        "rock": true,
        "scissors": false
    }
    scissors: {
        "rock": false,
        "paper": true
    }
}

And I get the users play, as well as the computers play. So to figure out who wins, I need to do something like this:

var userPlay = "rock";
var cpuPlay = "paper"; //this would be a function but for now lets simply it and just set it to "paper"

So to find the value for computing the winner, I need to go something like this:

var winner = winners[userPlay].cpuPlay;

But that always returns undefined. Obviously winners[userPlay].paper works, but I'm not sure how to use a variable to get to that final spot. Do I need to get the value of cpuPlay itself and use that?

Mihai Alexandru-Ionut · Accepted Answer · 2017-01-22T19:07:32.463

1

Your property name is stored in a variable called cpuPlay.

var cpuPlay = "paper";

To access the property you have to use bracket notation:

var winner = winners[userPlay][cpuPlay];

edited Jan 22 '17 at 19:07

answered Jan 22 '17 at 19:02

Mihai Alexandru-Ionut

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This works, thank you! I'll accept as soon as it lets me. – Daneel Rakow Jan 22 '17 at 19:03
@DaneelRakow, you're welcome ! Don't forget to accept answer. – Mihai Alexandru-Ionut Jan 23 '17 at 09:10

How do I get to a certain place in my JavaScript object using variables?

1 Answers1