How to return array of 50

Question

I am trying to return an array of object with 50 element inside of it

this what i am looking to achieve

  arrayofobject = [
    {
     id:0,
     Email: "Empty Email 0",
     Name: "Empty Name 0"
    },
    {
     id:1,
     Email: "Empty Email 1",
     Name: "Empty Name 1"
    }
............
 {
     id:49,
     Email: "Empty Email 49",
     Name: "Empty Name 49"
    }
]

I used the code below but still not able to achieve the result

var arrayofobject = []

for(var i = 0; i<=50; i++){
  arrayofobject.push("id" + i)
 arrayofobject.push("email"  + i)
 arrayofobject.push("name" + i)
}

i tried diffrent approch but i am still having a hard time to get the needed result

also you are pushing 3 different values each iteration instead of an object with 3 properties — Pete, Mar 27 '18 at 09:05
https://stackoverflow.com/questions/3895478/does-javascript-have-a-method-like-range-to-generate-an-array-based-on-suppl — georg, Mar 27 '18 at 10:00

score 8 · Answer 1 · edited Mar 27 '18 at 11:05

8

This should work for you:

var objects = [];
var n = 0;
while( n < 50 ){
  objects.push({
    id: n,
    email: 'email' + n,
    name: 'name' + n,
  });
  n++;
}
console.log(objects);

edited Mar 27 '18 at 11:05

Douwe de Haan

6,247
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answered Mar 27 '18 at 09:05

BRO_THOM

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4

You should usually use `for` instead of `while` when there is a known number of iterations like in this example. And even when you'd like to use `while` you could increase `n` directly in the condition like `while (n++ < 50) { ... ` – Benjamin Lüscher Mar 27 '18 at 09:24
This was the most simple, and readable example I could come up. OP isn't an expert so I wanted something that was readable and explained what it did just by looking at it. – BRO_THOM Mar 27 '18 at 09:26
2

OK I do understand your intend, but I would prefer the for-loop in this example (also for beginners) because it's best practice. – Benjamin Lüscher Mar 27 '18 at 09:34

score 6 · Answer 2 · edited Mar 27 '18 at 10:24

6

var arrayOfObjects = [];
    
for (var i = 0; i < 50; i++) {
  var newObj = {
    id: i,
    email: "Empty email " + i,
    name: "Empty name " + i
  }

  arrayOfObjects.push(newObj);
}

console.log(arrayOfObjects);

edited Mar 27 '18 at 10:24

Ben Thomas

3,180
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answered Mar 27 '18 at 09:10

Mick

837
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score 5 · Accepted Answer · edited Mar 27 '18 at 09:22

5

Use array.from its the best approach for that kind of situation

const result = Array.from({ length: 50 }, (x, z) => [
  { id: z }, { email: "Empty User " + z },{name: "Empy Name " + z}
]);

console.log(result)

edited Mar 27 '18 at 09:22

Salman A

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answered Mar 27 '18 at 09:05

Abslen Char

3,071
3
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2

Isn't obvious that this produces output different from what OP wants? – dfsq Mar 27 '18 at 09:06
He wants the ID, EMAIL and NAME In the same object, not different ones. Update your answer please, so he can your option too. – besciualex Mar 27 '18 at 09:06
besides what @dfsq says, I think this code is not all the readable for someone who (probably) is a beginner like OP. – BRO_THOM Mar 27 '18 at 09:07
please no change answer this is the code i need i had error in my question – Josh Miller Mar 27 '18 at 09:08
@BRO_THOM Indeed it doesn't has a beginner's style, but is also helpful. It can show him two different approaches with the same output. – besciualex Mar 27 '18 at 09:08
@JoshMiller what do you mean ? – Abslen Char Mar 27 '18 at 09:09
@AbdeslemCharif He wrote the expected output bad. Apparently he want what you posted 'by mistake'. – besciualex Mar 27 '18 at 09:09
Ahaha, if this is what OP indeed wants then I guess OP doesn't understand that this structure is not very usable. But who knows. – dfsq Mar 27 '18 at 09:10
I want array inside array array and then object inside this array same console log like this one – Josh Miller Mar 27 '18 at 09:11
1

@JoshMiller if you want a diffrent answer please edit your question – Abslen Char Mar 27 '18 at 09:13

score 3 · Answer 4 · edited Mar 27 '18 at 10:12

3

   let arrayofobject=[];
   for(var i = 0; i<50; i++){
       let a = {};
       a.id = "id"+i;
       a.email = "email"+i;
       a.name = "name"+i;
       arrayofobject.push(a);
    }
    console.log(arrayofobject);

edited Mar 27 '18 at 10:12

Deepu Reghunath

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answered Mar 27 '18 at 09:06

KoIIIeY

533
1
7
26

1

This will output 51 items. – BRO_THOM Mar 27 '18 at 09:09

T.J. Crowder · Answer 5 · 2018-03-27T09:24:45.483

You're pushing individual values. What you want is an array of objects.

In ES5 and earlier:

var arrayofobject = [];
for(var i = 0; i < 50; i++){ // Note <, not <=, if you want 0-49
    arrayofobject.push({
        id: i,
        email: "Empty Email " + i,
        name: "Empty Name " + i
    });
}
console.log(arrayofobject);

.as-console-wrapper {
  max-height: 100% !important;
}

In ES2015+, you can use Array.from's callback (it can also be polyfilled):

let arrayofobject = Array.from({length: 50}, (_, i) => {
    return {
        id: i,
        email: "Empty Email " + i,
        name: "Empty Name " + i
    };
});
console.log(arrayofobject);

.as-console-wrapper {
  max-height: 100% !important;
}

or with a concise function body:

let arrayofobject = Array.from({length: 50}, (_, i) => ({
    id: i,
    email: "Empty Email " + i,
    name: "Empty Name " + i
}));
console.log(arrayofobject);

.as-console-wrapper {
  max-height: 100% !important;
}

score 1 · Answer 6 · answered Mar 27 '18 at 09:07

Your condition should be i<50 and not i<=50 if you want id till 49 only. Also, you need to create a object with those properties and push it to the arrayofobject array like below:

var arrayofobject = []

for(var i = 0; i<50; i++){
  var obj = {};
  obj["id"] = i;
  obj["Email"] = "Empty Email " + i;
  obj["Name"] = "Empty Name " + i;
  arrayofobject.push(obj);
}

console.log(arrayofobject);

score 1 · Answer 7 · answered Mar 27 '18 at 09:08

You are currently pushing 3 object by iteration.

arrayofobject.push("id" + i) //Add 1 element
arrayofobject.push("email"  + i)//Add 1 element
arrayofobject.push("name" + i)//Add 1 element

You should only push one object like below

var arrayofobject = []

for (var i = 0; i <= 49; i++) {
  arrayofobject.push({
    id: i,
    Email: "Empty Email " + i,
    Name: "Empty Name " + i
  });
}

console.log(arrayofobject)

score 1 · Answer 8 · answered Mar 27 '18 at 11:10

1

var arrayList = [];
var uptoCount = 50;
for (var i = 0; i < uptoCount; i++) {
  var tempObj = {
    id: i,
    email: "Empty email " + i,
    name: "Empty name " + i
  }

  arrayList.push(tempObj);
}

console.log(arrayList);

answered Mar 27 '18 at 11:10

mayur kasar

165
6

score 0 · Answer 9 · answered Mar 27 '18 at 12:47

An alternate clean solution would be using array fill and map:

arr = Array(50).fill(0).map((val, index) => ({
     id: val + index,
     Email: "Empty Email " + (val + index),
     Name: "Empty Name " + (val + index)
    }));
console.log(arr);

But if you are making high performance JS application, and if you work with big/huge arrays, Array.map(..) creates big overload in both - memory and processor use, as it creates a copy of array.

Classic For loop is recommended as everyone else suggested.

How to return array of 50

9 Answers9