create javascript object with key and value from variables

Question

I've been reading up on javascript and I this site has helped me quite a lot. My goal is to create a javascript object with the "key, value" pair coming from variables. For starters I am trying to create the following javascript object, If I create like this:

    var tester = {
        person : "Sarah",
        friends : ["Tom", "Nils"],
        parents : ["Sandra", "Peter"]
    };

That works fine. However trying a different approach:

var tester = {};
var person = "Sarah";
var friendsArr = ["Tom", "Nils"];
var parentsArr = ["Sandra", "Peter"];

tester[person] = person;
tester[friends] = friendsArr;
tester[parents] = parentsArr;

That doesn't work. What am I doing wrong?

Jon · Accepted Answer · 2016-10-31 00:05:22Z

2

Change it to this:

tester['person'] = person;
tester['friends'] = friendsArr;
tester['parents'] = parentsArr;

or alternatively:

tester.person = person;
tester.friends = friendsArr;
tester.parents = parentsArr;

answered Oct 31, 2016 at 0:05

Jon

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Comments

Brando · Accepted Answer · 2016-10-31 00:05:27Z

1

You can use dot notation to assign the object keys.

var tester = {};
var person = "Sarah";
var friendsArr = ["Tom", "Nils"];
var parentsArr = ["Sandra", "Peter"];

tester.person = person;
tester.friends = friendsArr;
tester.parents = parentsArr

answered Oct 31, 2016 at 0:05

Brando

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Comments

Parshuram Kalvikatte · Accepted Answer · 2016-10-31 04:32:44Z

0

I think you need to defined the property of the object as an array

Here is your answer

var tester = {};
var person = "Sarah";
var friendsArr = ["Tom", "Nils"];
var parentsArr = ["Sandra", "Peter"];

tester.person = person;
tester.friends = [];
tester.parents = [];
tester.friends = friendsArr;
tester.parents = parentsArr

One thing i need to suggest to all javascript developers.You need to be very carefull while working with arrays.

If you assign a array directly for eg :-tester.friends = friendsArr This will create a reference to friendsArr Object so any change in tester.friends will ultimate cause an change in friendsArr Best way is to create a new array instance and push variable inside.

answered Oct 31, 2016 at 4:32

Parshuram Kalvikatte

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