Not able to insert object into array of json object

Question

Excuse me for this simple problem - but I seem to miss something obvious.Any pointer would be a great help.

I have a JSON like

var  whatever = [{           
"key1" : { "text" : "text1","group"  : "1" },
"key2" : { "text" : "text2","group"  : "2" },
"key3" : { "text" : "text3","group"  : "3" }
}];

I am trying to add another object(at start preferably) - but just couldn't get it to work.

var str = '{"text":"text0","group":"0"}';
var obj = JSON.parse(str);
whatever[0].put("key0",obj);

Getting the below error:

Uncaught TypeError: whatever[0].put is not a function

fiddle

Object properties do not have an order, so adding it "at the start" makes no sense. — Jamiec
– Jamiec, Commented Sep 22, 2017 at 8:31
The error was pretty clear. Don't take this as being rude, but you should really try harder to understand what the interpreter/compiler tells you. As for javascript opening a console writing 'obj.' shows you completion that are really helpful as a first source of documentation — ilmirons
– ilmirons, Commented Sep 22, 2017 at 8:35
@NinaScholz I was trying to order the entries but after going through the replies - I realize that this is not the best way to go about it. — Soumya
– Soumya, Commented Sep 22, 2017 at 9:15

Suren Srapyan · Accepted Answer · 2017-09-22 08:43:31Z

3

There is no put function on the object. Use property instead of it. When you want to assign to a property which does not exist, it creates a new one and assigns the value to it.

whatever[0]["key0"] = obj;

What is related to at start preferably, there is no order for object properties. It is a wrong statement. If you want ordering try to think from the view of array of objects instead of array of object, which contains objects.

Code examples

const whatever = [{           
   "key1" : { "text" : "text1","group"  : "1" },
   "key2" : { "text" : "text2","group"  : "2" },
   "key3" : { "text" : "text3","group"  : "3" }
}];

const str = '{ "text" : "text0", "group" : "0" }';
const obj = JSON.parse(str);

whatever[0]["key0"] = obj;

console.log(whatever);

Or use Object#assign

const whatever = [{           
   "key1" : { "text" : "text1","group"  : "1" },
   "key2" : { "text" : "text2","group"  : "2" },
   "key3" : { "text" : "text3","group"  : "3" }
}];

const str = '{ "text" : "text0", "group" : "0" }';
const obj = JSON.parse(str);

Object.assign(whatever[0], { key0: obj }) // this will also change the object

console.log(whatever);

My suggestion is to use an array of objects, if you want something with order.

const whatever = [
   { "text" : "text1","group"  : "1" },
   { "text" : "text2","group"  : "2" },
   { "text" : "text3","group"  : "3" }
];

const str = '{ "text" : "text0", "group" : "0" }';
const obj = JSON.parse(str);

// Add to the start
whatever.unshift(obj);
console.log(whatever);

// Add to the end
whatever.push(obj);
console.log(whatever);

edited Sep 22, 2017 at 8:43

answered Sep 22, 2017 at 8:30

Suren Srapyan

68.9k14 gold badges128 silver badges119 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Adrian Over a year ago

Technically wrong, "at start preferably" yours will add it to the end. unshift() to append to the front of an array should be used.

Suren Srapyan Over a year ago

@Adriani6 Didn't look at that part. Edited

Adrian Over a year ago

Perfect, Now it's a complete answer.

Soumya Over a year ago

Perfect explanation.I stand corrected on the way how to order.I will modify it accordingly straight away.Thanks a lot.

marvel308 · Accepted Answer · 2017-09-22 08:32:18Z

1

maybe you want something like this

var  whatever = [{           
"key1" : { "text" : "text1","group"  : "1" },
"key2" : { "text" : "text2","group"  : "2" },
"key3" : { "text" : "text3","group"  : "3" }
}];

Object.assign(whatever[0], {key4 : { "text" : "text4","group"  : "4" }});

console.log(whatever);

answered Sep 22, 2017 at 8:32

marvel308

10.5k3 gold badges24 silver badges32 bronze badges

Collectives™ on Stack Overflow

Not able to insert object into array of json object

2 Answers 2

4 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related