javascript print nested object using for loop?

Question

how do i print out all the person in the person object?

For Example i want my output to be like this.

John Doe 25

Paul Vosper 23

 var txt = "";
 var person = {
            p1: {fname:"John", lname:"Doe", age:25},
            p2: {fname:"Paul", lname:"Vosper", age:23}
           }; 
  var x;
  for (x in person) 
  {
    txt += person[x] + " ";
  }
  document.getElementById("demo").innerHTML = txt;

Josh Beam · Accepted Answer · 2015-08-24 02:56:09Z

3

You can do a map/join:

var txt = Object.keys(person).map(function(k) {
  var p = person[k];

  return [p.fname, p.lname, p.age].join(' ');
}).join(' ');

Output in the console:

If you want a line break element (<br>) between them, just join on a <br>:

document.getElementById("demo").innerHTML = Object.keys(person)
                                            .map(combineAllProperties)
                                            .join('<br>');

function combineAllProperties(k) {
  var p = person[k];

  return [p.fname, p.lname, p.age].join(' ');
}

edited Aug 24, 2015 at 2:56

answered Aug 24, 2015 at 2:50

Josh Beam

19.9k5 gold badges48 silver badges69 bronze badges

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

2 Comments

Mebighobo Over a year ago

so the only way to do it is to write a separate function to combine and print it? you cant just iterate an object in an object and print?

Josh Beam Over a year ago

@Mebighobo, you can just iterate and print, but the way I've suggested is a semantic programming paradigm (the algorithm you're trying to implement is fundamentally a map/join, and JavaScript supplies those methods out of the box). It's not a "separate" function, it's a callback to the map method.

RobG · Accepted Answer · 2015-08-24 03:14:04Z

1

You can use Array.prototype.reduce in conjunction with Object.keys:

var person = {
  p1: {fname:"John", lname:"Doe", age:25},
  p2: {fname:"Paul", lname:"Vosper", age:23}
};

document.write(Object.keys(person).reduce(function(s, p, i) {
  var o = person[p];
  return s + (i>0?'<br>':'') + o.fname + ' ' + o.lname + ' ' + o.age
  }, '')
);

answered Aug 24, 2015 at 3:14

RobG

148k32 gold badges180 silver badges216 bronze badges

Collectives™ on Stack Overflow

javascript print nested object using for loop?

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related