If you want to map objects to something (in this case a property). I think Array.prototype.map is what you're looking for if you want to code functionally.
(fiddle)
If you want to support older browsers, that are not ES5 compliant you can shim it (there is a polyfill on the MDN page above). Another alternative would be to use underscorejs's pluck method:
var users = [
{name: "Joe", age: 22},
{name: "Kevin", age: 24},
{name: "Peter", age: 21}
];
var result = _.pluck(users,'name').join(",")
Top answer 1 of 14
698
If you want to map objects to something (in this case a property). I think Array.prototype.map is what you're looking for if you want to code functionally.
(fiddle)
If you want to support older browsers, that are not ES5 compliant you can shim it (there is a polyfill on the MDN page above). Another alternative would be to use underscorejs's pluck method:
var users = [
{name: "Joe", age: 22},
{name: "Kevin", age: 24},
{name: "Peter", age: 21}
];
var result = _.pluck(users,'name').join(",")
2 of 14
93
Well you can always override the toString method of your objects:
var arr = [
{name: "Joe", age: 22, toString: function(){return this.name;}},
{name: "Kevin", age: 24, toString: function(){return this.name;}},
{name: "Peter", age: 21, toString: function(){return this.name;}}
];
var result = arr.join(", ");
console.log(result);MDN Web Docs
developer.mozilla.org › en-US › docs › Web › JavaScript › Reference › Global_Objects › Array › join
Array.prototype.join() - JavaScript - MDN Web Docs
The join() method of Array instances returns a new string that is the concatenation of all elements in this array, separated by commas or a specified separator string. If the array has only one item, that item's stringification is returned without using the separator.
javascript - Join array of objects - Stack Overflow
Code partly taken from accepted answer in: How can I merge properties of two JavaScript objects dynamically? More on stackoverflow.com
javaScript Array.join("")
The join() method creates and returns a new string by concatenating all of the elements in an array (or an array-like object), separated by commas or a specified separator string. If the array has only one item, then that item will be · So “creates and returns a new string” says nothing ... More on forum.freecodecamp.org
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0
November 3, 2022Merge Array of objects that have the same properties
I am retaining your spelling quirks here. First create an object whose keys are the student IDs: const studentsByID = Students.reduce( (obj, { ID, Name, SponserID, SponserName }) => { if (!obj.hasOwnProperty(ID)) { obj[ID] = { ID, Name, Sponsers: [] }; } obj[ID].Sponsers = [ ...obj[ID].Sponsers, { SponserID, SponserName } ]; return obj; }, {} ); Then your desired result is its values: const ModifiedStudents = Object.values(studentsByID); More on reddit.com
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January 22, 2022How can I merge two arrays of different objects but equal length?
Use the spread operator to merge objects, and do so in a loop: mergedArray = [] for (let i = 0; i < arrayOne.length; i++) { newObject = {...arrayOne[i], ...arrayTwo[i] } mergedArray.push(newObject) } More on reddit.com
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March 24, 2021W3Schools
w3schools.com › jsref › jsref_join.asp
JavaScript Array join() Method
The join() method returns an array as a string.
Codemzy
codemzy.com › blog › array-join-object-property
Using Array join() on an object property - Codemzy's Blog
May 30, 2023 - I've added a space after the comma by passing a string (", ") to .join() to use as the separator. Let's break that down so it's really clear what is happening at each stage. // the array of objects let names = [ { first: "Roger", last: "McRogerson" }, { first: "Peter", last: "Peterson" }, { first: "Jane", last: "Janeson" } ]; // create an array of the property values you need as strings let namesValues = names.map((name) => `${name.first} ${name.last}`); console.log(namesValues); // ["Roger McRogerson", "Peter Peterson", "Jane Janeson"] // join them to become a string with a comma separator let joinedNames = namesValues.join(", "); console.log(joinedNames); // "Roger McRogerson, Peter Peterson, Jane Janeson"
Board Infinity
boardinfinity.com › blog › array-join-in-javascript
Array Join() in JavaScript | Board Infinity
January 2, 2025 - The use of javascript array join() is to combine all the elements of an array and form a new string out of the array.
daily.dev
daily.dev › home › blog › webdev › javascript join() method: syntax, examples & pitfalls
JavaScript join() Method: Syntax, Examples & Pitfalls | daily.dev
May 25, 2026 - The Array join() method converts arrays to strings with a custom separator. Covers syntax, handling null/undefined, performance in loops
Medium
arek-jaworski.medium.com › how-to-join-two-arrays-of-objects-into-one-with-javascript-ab70d467cedd
How to join two arrays of objects into one with JavaScript | by Arek Jaworski | Medium
July 4, 2019 - We want to join them together into ... 'd', 'e', 'f'] We can achieve that easily with plain javascript and Array.prototype.concat() method:...
Top answer 1 of 3
1
Edited to reflect that b can be smaller but never larger than a.
function merge(a,b){
//Don't want to mutate a
var result = a.slice();
for(var i = 0; i < b.length; i++){
for (var attrname in b[i]) {
result[i][attrname] = b[i][attrname];
}
}
return result;
}
Code partly taken from accepted answer in: How can I merge properties of two JavaScript objects dynamically?
2 of 3
1
Assuming that the two arrays have the same length, an in place merge could be something like this:
var a = [{ x: 0, y: 0, color: "green", value: undefined, weight: 1 }, { x: 0, y: 1, color: "red", value: undefined, weight: 1 }];
var b = [{ x: 0, y: 0, value: 1, weight: 1 }, { x: 0, y: 1, value: 3, weight: 1 }];
function merge_objects(o1, o2) {
Object.keys(o2).forEach(
function(key) {
o1[key] = o2[key];
});
}
function merge(a, b) {
if (a.length != b.length) {
throw new Error();
}
for (var ix=0; ix<a.length; ix++) {
merge_objects(a[ix], b[ix]);
}
}
MDN Web Docs
developer.mozilla.org › en-US › docs › Web › JavaScript › Reference › Global_Objects › Array › concat
Array.prototype.concat() - JavaScript - MDN Web Docs
Then, for each argument, its value will be concatenated into the array — for normal objects or primitives, the argument itself will become an element of the final array; for arrays or array-like objects with the property Symbol.isConcatSpreadable set to a truthy value, each element of the argument will be independently added to the final array.
Go Make Things
gomakethings.com › merging-arrays-and-objects-with-vanilla-javascript
Merging arrays and objects with vanilla JavaScript | Go Make Things
January 4, 2023 - You can alternatively use the spread operator (...) to create a new array with the values of your other arrays. ... You can use the Object.assign() method to merge two or more objects together.
W3Resource
w3resource.com › javascript › object-property-method › array-join.php
Array Object - JavaScript join() Method
var fruits = new Array("Orange", "Apple", "Banana", "Chery"); var fruitslist1=fruits.join(); var newParagraph = document.createElement("p"); var newText = document.createTextNode("Fruits List : " + fruitslist1 ); newParagraph.appendChild(newText); document.body.appendChild(newParagraph); var fruitslist2=fruits.join(', '); var newParagraph1 = document.createElement("p"); var newText1 = document.createTextNode("Fruits List : " + fruitslist2); newParagraph1.appendChild(newText1); document.body.appendChild(newParagraph1); var fruitslist3=fruits.join('-'); var newParagraph2 = document.createElement
ReqBin
reqbin.com › code › javascript › 98ugueow › javascript-array-join-example
How do I join array elements in JavaScript?
To join JavaScript array elements in a string, you can use the array.join(separator) method.
GeeksforGeeks
geeksforgeeks.org › javascript › javascript-array-join-method
JavaScript Array join() Method - GeeksforGeeks
January 16, 2026 - The JavaScript join() method is used to combine all elements of an array into a single string.
xjavascript
xjavascript.com › blog › perform-join-on-value-in-array-of-objects
How to Perform .join() on Values in an Array of Objects by Property in JavaScript — xjavascript.com
Joining values from an array of objects by property is a common task in JavaScript, and the solution is surprisingly simple: use map() to extract the property values into a primitive array, then join() to combine them into a string.
DEV Community
dev.to › shubhamtiwari909 › join-in-javascript-4050
Array Methods in JS - join() - DEV Community
August 21, 2022 - It is used to join the elements of array and returns them as a string Example - arr -> ["A","B","C","D"] After applying join() method on this array result -> A,B,C,D ... const emptyArray = [] const numberArray = [1,2,3,4,5]; const stringArray ...
GeeksforGeeks
geeksforgeeks.org › javascript › how-to-merge-two-different-arrays-of-objects-with-unique-values-only-in-javascript
How to Merge two Different Arrays of Objects with Unique Values in JavaScript? - GeeksforGeeks
August 5, 2025 - The reduce() method is used to iteratively merge array2 into array1. The some() method is employed to check if an object with the same id already exists in the accumulated array.
GeeksforGeeks
geeksforgeeks.org › javascript › how-to-merge-multiple-array-of-object-by-id-in-javascript
How to Merge Multiple Array of Object by ID in JavaScript? - GeeksforGeeks
August 23, 2024 - [ { id: 1, name: 'HTML', popularity: 'High' }, { id: 2, name: 'CSS', popularity: 'Medium' }, { id: 3, name: 'JavaScript' } ] The reduce method provides a concise and functional way to merge arrays by accumulating results during iteration. In this approach, reduce iterates over each object in the first array, using find to locate a corresponding object in the second array based on the ID. When a match is found, the two objects are merged and added to the accumulator array. After processing all elements, the final merged array is returned, offering a streamlined solution for combining objects from multiple arrays
Greenroots
blog.greenroots.info › 5-ways-to-merge-arrays-in-javascript-and-their-differences
5 ways to merge arrays in JavaScript and their differences
October 15, 2021 - In this article, we will learn five different ways to merge arrays in JavaScript. We will also conclude which is the best way among all and when to use it. If you like to learn from video content as well, this article is also available as a video tutorial here: 🙂 ... Alright, let's get started. Using the for loop to merge two or more array elements may be the most viable way. Most of us are aware of how to use for-loops in programming.
YouTube
youtube.com › watch
JavaScript join method: How to merge arrays into one value - YouTube
In this tutorial we’ll look at the JavaScript join method and see how it can be used to merge an array in to one single value.Don’t forget to subscribe to th...
Published: January 30, 2019
freeCodeCamp
forum.freecodecamp.org › curriculum help
javaScript Array.join("") - Curriculum Help - The freeCodeCamp Forum
November 3, 2022 - The join() method creates and returns a new string by concatenating all of the elements in an array (or an array-like object), separated by commas or a specified separator string.