How to do .forEach() for object in javascript? [duplicate]

Question

I have a data structure similar to:

var object = {
  name: "a",
  number: "1",
  mission: ['a','b','c']
}

Now I want to update them into the database so I need to walk them.

I tried:

object.forEach(function(value, key, map){
  console.log('value: ' + value + ', key: ' + key + ', map:' + map);
});

And then the console report an error: object.forEach is not a function

forEach should be invoked on arrays not with an object. If you try on array of objects , it will work — Sridhar
– Sridhar, Commented May 31, 2017 at 4:50
In modern JS Object.entries(object).forEach(([key, value]) => console.log(`key: ${key}, value: ${value}`)); With polyfills and transpilers this should run anywhere :p — Jaromanda X
– Jaromanda X, Commented May 31, 2017 at 4:55
This is not a very good duplicate, because (1) no answers mention Object.entries and (2) it is mainly about chunking. — user663031
– user663031, Commented May 31, 2017 at 5:14

Anurag Awasthi · Accepted Answer · 2017-05-31 05:01:25Z

14

Try this,

Object.keys(object).forEach(key=>{
    console.log(key ,object[key]);
})

edited May 31, 2017 at 5:01

answered May 31, 2017 at 4:50

Anurag Awasthi

6,2532 gold badges21 silver badges34 bronze badges

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

3 Comments

Aero Wang Over a year ago

thanks, how do i output map? also this seems to flat array into string...

Anurag Awasthi Over a year ago

@AeroWang well inforEach third argument is actual array itself on which you have called forEach. Array is converting into string because we are adding it with a string.

Aero Wang Over a year ago

how to keep it as an array?

sudo · Accepted Answer · 2017-05-31 04:53:38Z

0

You could do it like this.

var object = {
  name: "a",
  number: "1",
  mission: ['a','b','c']
}
for(var key in object) console.log(key, object[key]);

answered May 31, 2017 at 4:53

sudo

3233 silver badges12 bronze badges

2 Comments

Aero Wang Over a year ago

thanks, how do i output map? also this seems to flat array into string...

einpoklum Nov 17 at 19:53

Why var rather than let or const?

Manav Sharma · Accepted Answer · 2017-05-31 04:57:20Z

-1

Use this,

 for (var item in object) {
    console.log('value: ' + object['name'] + ', key: ' + object['number'] + ', map:' + object['mission']);
 }

answered May 31, 2017 at 4:57

Manav Sharma

1871 silver badge8 bronze badges

2 Comments

Aero Wang Over a year ago

no, the key in the object will change, they might not be name, number, and mission

user663031 Over a year ago

Why are you looping over the keys with item, but then not doing anything with it?

Collectives™ on Stack Overflow

How to do .forEach() for object in javascript? [duplicate]

3 Answers 3

3 Comments

2 Comments

2 Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

3 Comments

2 Comments

2 Comments

Linked

Related