# Iterate unknown named object properties
**URL:** https://discourse.processing.org/t/iterate-unknown-named-object-properties/23137
**Category:** Coding Questions
**Created:** [August 8, 2020, 12:34pm UTC](https://discourse.processing.org/t/iterate-unknown-named-object-properties/23137 "2020-08-08T12:34:03Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@ZAF](https://discourse.processing.org/u/ZAF)
#### Post date: [August 8, 2020, 12:34pm UTC](https://discourse.processing.org/t/iterate-unknown-named-object-properties/23137/1 "2020-08-08T12:34:03Z")
Hi, im working on a function called howMuchOn(users) wich recieves an
object filled with objects as the following example shows:
let users = {
toni: {
age: 33,
online: true
},
emily: {
age: 25,
online: true
},
frank: {
age: 25,
online: false
},
henry: {
age: 24,
online: false
}
};
I need to get out of there just how mucho online:true there are.
Since i actually dont know the names that will come within the main object, i don’t know how to access the property “online” within object “name” within object “users”.
My function simplified looks like this (the question marks ‘???’ is where im stucked) :
function howMuchOn(users) {
var usersOn = 0;
for (var i = 0; i \< users.length; i++) {
if ( usuarios.???.online === true){
usersOn += 1;
}
}
return usersOn;
}
I couldnt solve it with for…in loop eather, even tried Object.keys(users) to get an array of the names but couldnt use that array of strings to acces-
Is something like this posible? :
```
users[array[0]].online
```
I insist, its objects within an object, not an array of objects.
Thanks!
---
### Author:  [@GoToLoop](https://discourse.processing.org/u/GoToLoop)
#### Post date: [August 9, 2020, 1:39am UTC](https://discourse.processing.org/t/iterate-unknown-named-object-properties/23137/2 "2020-08-09T01:39:34Z")
> [@ZAF](#):
>
> , it’s objects within an object, not an array of objects.
Yea, kinda 2d obj{}{} rather than 2d arr. Got it!
> [@ZAF](#):
>
> I couldn’t solve it with `for…in` loop either, even tried `Object.keys(users)`…
Those are correct approaches in order to traverse the outer dimension of the 2d object container.
On the sketch below, I’m using a `for...in` loop in order to return all inner objects which are _online_ as an array container:
> **[for...in - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in)**
>
> The for...in statement iterates over all enumerable string properties of an object (ignoring properties keyed by symbols), including inherited enumerable properties.
```auto
/**
* Traverse 2D Object Container (v1.0.0)
* GoToLoop (2020-Aug-08)
* Discourse.Processing.org/t/iterate-unknown-named-object-properties/23137/2
*/
'use strict';
var usersOn, users = {
Tony: {
age: 33,
online: true
},
Emily: {
age: 25,
online: true
},
Frank: {
age: 25,
online: false
},
Henry: {
age: 24,
online: false
}
};
usersOn = usersOnlineForIn(users);
console.info('for...in loop version:');
console.log(`There are ${usersOn.length} users online.`);
console.table(usersOn);
function usersOnlineForIn(users) {
const usersOn = [];
for (const key in users) {
const user = users[key];
user && user.online && usersOn.push(user);
}
return usersOn;
}
```
Given it’s vanilla JS code, you can just open a browser’s console and paste the whole code there.
Notice that within the loop block:
```auto
for (const key in users) {
const user = users[key];
user && user.online && usersOn.push(user);
}
```
I use the _key_ iterator as the index for the _users{}{}_ container:
`const user = users[key];`
We can also use a `for...of` loop for it:
> **[for...of - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of)**
>
> The for...of statement executes a loop that operates on a sequence of values sourced from an iterable object. Iterable objects include instances of built-ins such as Array, String, TypedArray, Map, Set, NodeList (and other DOM collections), as well...
Together w/ Object.**keys()**:
> **[Object.keys() - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys)**
>
> The Object.keys() static method returns an array of a given object's own enumerable string-keyed property names.
For the same result as in [`for...in`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in) loop solution:
```auto
usersOn = usersOnlineObjKeys(users);
console.info('for...of + Object.keys() version:');
console.log(`There are ${usersOn.length} users online.`);
console.table(usersOn);
function usersOnlineObjKeys(users) {
const usersOn = [];
for (const key of Object.keys(users)) {
const user = users[key];
user && user.online && usersOn.push(user);
}
return usersOn;
}
```
Likewise, Object.**entries()** can get us there too:
> **[Object.entries() - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries)**
>
> The Object.entries() static method returns an array of a given object's own enumerable string-keyed property key-value pairs.
```auto
usersOn = usersOnlineObjEntries(users);
console.info('for...of + Object.entries() version:');
console.log(`There are ${usersOn.length} users online.`);
console.table(usersOn);
function usersOnlineObjEntries(users) {
const usersOn = [];
for (const [, user] of Object.entries(users))
user.online && usersOn.push(user);
return usersOn;
}
```
However, if you don’t care to grab an array of _online_ objects and just wanna count how many of them are _online_, the shortest code is via Object.**values()**:
> **[Object.values() - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/values)**
>
> The Object.values() static method returns an array of a given object's own enumerable string-keyed property values.
```auto
usersOn = howManyUsersOnlineObjValues(users);
console.info('for...of + Object.values() w/o array version:');
console.log(`There are ${usersOn} users online.`);
function howManyUsersOnlineObjValues(users) {
var usersOn = 0;
for (const { online } of Object.values(users)) online && ++usersOn;
return usersOn;
}
```
Although Object.[**values()**](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/values) can also be used to return an array of _online_ objects just like the Object.[**entries()**](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries) approach:
```auto
usersOn = usersOnlineObjValues(users);
console.info('for...of + Object.values() version:');
console.log(`There are ${usersOn.length} users online.`);
console.table(usersOn);
function usersOnlineObjValues(users) {
const usersOn = [];
for (const user of Object.values(users)) user.online && usersOn.push(user);
return usersOn;
}
```
Here is the 5 complete approaches in 1 sketch:
```auto
/**
* Traverse 2D Object Container (v1.0.2)
* GoToLoop (2020-Aug-08)
* Discourse.Processing.org/t/iterate-unknown-named-object-properties/23137/2
*/
'use strict';
var usersOn, users = {
Tony: {
age: 33,
online: true
},
Emily: {
age: 25,
online: true
},
Frank: {
age: 25,
online: false
},
Henry: {
age: 24,
online: false
}
};
usersOn = usersOnlineForIn(users);
console.info('for...in loop version:');
console.log(`There are ${usersOn.length} users online.`);
console.table(usersOn);
usersOn = usersOnlineObjKeys(users);
console.info('for...of + Object.keys() version:');
console.log(`There are ${usersOn.length} users online.`);
console.table(usersOn);
usersOn = usersOnlineObjEntries(users);
console.info('for...of + Object.entries() version:');
console.log(`There are ${usersOn.length} users online.`);
console.table(usersOn);
usersOn = usersOnlineObjValues(users);
console.info('for...of + Object.values() version:');
console.log(`There are ${usersOn.length} users online.`);
console.table(usersOn);
usersOn = howManyUsersOnlineObjValues(users);
console.info('for...of + Object.values() w/o array version:');
console.log(`There are ${usersOn} users online.`);
function usersOnlineForIn(users) {
const usersOn = [];
for (const key in users) {
const user = users[key];
user && user.online && usersOn.push(user);
}
return usersOn;
}
function usersOnlineObjKeys(users) {
const usersOn = [];
for (const key of Object.keys(users)) {
const user = users[key];
user && user.online && usersOn.push(user);
}
return usersOn;
}
function usersOnlineObjEntries(users) {
const usersOn = [];
for (const [, user] of Object.entries(users))
user.online && usersOn.push(user);
return usersOn;
}
function usersOnlineObjValues(users) {
const usersOn = [];
for (const user of Object.values(users)) user.online && usersOn.push(user);
return usersOn;
}
function howManyUsersOnlineObjValues(users) {
var usersOn = 0;
for (const { online } of Object.values(users)) online && ++usersOn;
return usersOn;
}
```