Remove elements from javascript array by position - Stack Overflow

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I have a javascript array

var countries = ["India","USA","China","Canada","China"];

I want to remove "China" only from 2nd position, and return

var countries = ["India","USA","Canada","China"];

Something similar to java linkedlist.remove(index)

I have read following question but I don't know how to use it if there are duplicate elements in array. How do I remove a particular element from an array in JavaScript?

I have a javascript array

var countries = ["India","USA","China","Canada","China"];

I want to remove "China" only from 2nd position, and return

var countries = ["India","USA","Canada","China"];

Something similar to java linkedlist.remove(index)

I have read following question but I don't know how to use it if there are duplicate elements in array. How do I remove a particular element from an array in JavaScript?

• javascript
• arrays

Share Improve this question Follow edited May 23, 2017 at 10:24 CommunityBot 111 silver badge asked Apr 15, 2015 at 16:56 Pradip ShenolkarPradip Shenolkar 79711 gold badge1414 silver badges3434 bronze badges 5

• 1 are you looking for array.splice? – invernomuto Commented Apr 15, 2015 at 16:58
• @InvernoMuto I am not sure whether I can use array.splice in this situation. – Pradip Shenolkar Commented Apr 15, 2015 at 16:59
• You are Right, before to call splice you have to locate your "China" recurrence, you can use IndexOf otherwise LastIndexOf otherwise you havee to craft a custom IndexFilter – invernomuto Commented Apr 15, 2015 at 17:01
• you can definitely use str.indexOf(searchValue[, fromIndex]) where fromIndex is the starting recurrence of your value – invernomuto Commented Apr 15, 2015 at 17:03
• So many answers, not of which does what asked for. See my answer, it does exactly what you asked for – Sam Battat Commented Apr 15, 2015 at 17:11

Add a ment  | 

4 Answers 4

Sorted by: Reset to default 5

Try splice():

countries.splice(2,1);

Here, first argument is the position and second is the number of elements to remove.

To get the index use indexOf(), -1 if not found:

countries.indexOf("China");

So you have:

var i = countries.indexOf("China");
if(-1 !== i) {
    countries.splice(i, 1);
}

You can use a mix of array.indexOf and array.splice.

var countries = ["India","USA","China","Canada","China"];
var first_china = countries.indexOf("China");

if(first_china > -1){
    countries.splice(first_china , 1);
}

The question you linked also has the same answer (https://stackoverflow./a/5767357). indexOf will return you the index of the first match it finds. So if there are duplicates, it will still only remove the first one.

You can use the JavaScript Array splice() Method.

var countries = ["India", "USA", "China", "Canada", "China"];
document.getElementById("demo").innerHTML = countries;

function myFunction() {
  countries.splice(2, 1);
  document.getElementById("demo").innerHTML = countries;
}

<button onclick="myFunction()">SPLICE!</button>
<p id="demo"></p>

var c = ["India","USA","China","Canada","China"];
// provide the index you want to remove here (2)
var c2 = c.filter(function(item, idx) {if(idx != 2) return item;});

console.log(c2);

DEMO: http://jsfiddle/kf8epwnh/

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