How to get values in object using a loop index

Question

I have a javascript formset that submits multiple data, if I am getting all the post data, I have something like the below

firstname1: "John",
lastname1: "Doe",
firstname2: "Mary",
lastname2: "Allinson",
firstname3: "David"
lastname3: "Mark",
eventDesctiption: "Lorem Ipsum...",
eventDate: "Lorem Ipsum..."

I have an hidden field that holds the number of names submitted, in this case; its 3. I want to be able to loop through the names and put them in an array of objects before posting to an API, I want to be able to achieve the below

{
eventDesctiption: "Lorem Ipsum...",
eventDate: "Lorem Ipsum...",
people: [
    {firstname: "John", lastname: "Doe"},
    {firstname: "Mary", lastname: "Allinson"},
    {firstname: "David", lastname: "Mark"},
    ]
}

I tried the below, but it seem to concatenate the index with the value, which is not what I want

peopleArray = new Array();
for(var i=1; i<=no_of_ben; i++){
            var peopleObject = {};
            
            peopleObject.firstname = data.firstname + 'i';
peopleObject.lastname = data.lastname + 'i';
            peopleArray.push(peopleObject);
        }

How to do this without concatenating the index

Does this answer your question? [form serialize javascript (no framework)](https://stackoverflow.com/questions/11661187/form-serialize-javascript-no-framework) — emerson.marini, Sep 24 '20 at 09:04
You should submit data as an array of names, for example: `firstname[0] lastname[0]`, than you will have no issues. — skobaljic, Sep 24 '20 at 09:10
What is the `typeof data` in your example? Is it an object with fields `firstname1` and so on? — Anton, Sep 24 '20 at 09:20
Your js code is not working, right? So you want your `peopleArray` to save both `firstname` and `lastname` is it? — Kopi Bryant, Sep 24 '20 at 09:33
@skobaljic it is a formset, the way the data came wont allow that in the form — Temi 'Topsy' Bello, Sep 24 '20 at 10:51
@Temi'Topsy'Bello `eventDesctiption` it has a typo or it should be named like this? — Anton, Sep 24 '20 at 11:51

Anton · Accepted Answer · 2020-09-24T15:31:21.110

const input = {
  firstname1: "John",
  lastname1: "Doe",
  firstname2: "Mary",
  lastname2: "Allinson",
  firstname3: "David",
  lastname3: "Mark",
  eventDescription: "Lorem Ipsum...",
  eventDate: "Lorem Ipsum..."
};

const output = {
  eventDescription: input.eventDescription,
  eventDate: input.eventDate,
  people: []
};

const peopleCount = 3; // You said you have this one somewhere
for (let i = 1; i <= peopleCount; i++) {
  const onePerson = {
    firstname: input['firstname' + i],
    lastname: input['lastname' + i]
  };
  output.people.push(onePerson);
}

console.log(output);

score 0 · Answer 2 · answered Sep 24 '20 at 09:49

0

check if this works..

peopleArray = new Array();
for(var i=1; i<=no_of_ben; i++){
        var peopleObject = {};            
        peopleObject.firstname = data['firstname' + 'i'];
        peopleObject.lastname = data['lastname' + 'i'];
        peopleArray.push(peopleObject);
    }

replaced data.firstname + 'i' with data['firstname' + 'i']

answered Sep 24 '20 at 09:49

shotgun02

756
4
14

No, this wont work. Remember they all came in as object – Temi 'Topsy' Bello Sep 24 '20 at 10:08

score 0 · Answer 3 · answered Sep 24 '20 at 12:47

Try this. It should be work

peopleArray = new Array();
data = {
  firstname1: 'king', lastname1: 'James',
  firstname2: '2ndName', lastname2: '2ndLast',
  firstname3: 'alice', lastname3: 'bambam'
};

for(var i=1; i<=3; i++){
  var x = 'firstname';
  var y = 'lastname';
  var peopleObject = {};
  x = x + i;
  y = y + i;
  peopleObject.firstname = data[x];
  peopleObject.lastname = data[y];
  peopleArray.push(peopleObject);
}

console.log(peopleArray);

How to get values in object using a loop index

3 Answers3