Perform .join on value in array of objects

Question

If I have an array of strings, I can use the .join() method to get a single string, with each element separated by commas, like so:

[\"Joe\", \"         


        

Answer 1

lets say the objects array is referenced by the variable users

If ES6 can be used then the easiest solution will be:

users.map(user => user.name).join(', ');

If not, and lodash can be used so :

 _.map(users, function(user) {
     return user.name;
 }).join(', ');

Answer 2

I don't know if there's an easier way to do it without using an external library, but I personally love underscore.js which has tons of utilities for dealing with arrays, collections etc.

With underscore you could do this easily with one line of code:

_.pluck(arr, 'name').join(', ')

Answer 3

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(", ");
//result = "Joe, Kevin, Peter"

Answer 4

try this

var x= [
  {name: "Joe", age: 22},
  {name: "Kevin", age: 24},
  {name: "Peter", age: 21}
]

function joinObj(a, attr) {
  var out = []; 
  for (var i=0; i<a.length; i++) {  
    out.push(a[i][attr]); 
  } 
 return out.join(", ");
}

var z = joinObj(x,'name');
z > "Joe, Kevin, Peter"
var y = joinObj(x,'age');
y > "22, 24, 21"