How can I remove a specific item from an array?

2011-04-24 javascript arrays

I have an array of numbers and I'm using the .push() method to add elements to it.

Is there a simple way to remove a specific element from an array?

I'm looking for the equivalent of something like:

array.remove(number);

I have to use core JavaScript. Frameworks are not allowed.

Answers

Array.prototype.remByVal = function(val) {
    for (var i = 0; i < this.length; i++) {
        if (this[i] === val) {
            this.splice(i, 1);
            i--;
        }
    }
    return this;
}
//Call like
[1, 2, 3, 4].remByVal(3);

Array.prototype.remByVal = function(val) {
    for (var i = 0; i < this.length; i++) {
        if (this[i] === val) {
            this.splice(i, 1);
            i--;
        }
    }
    return this;
}

var rooms = ['hello', 'something']

rooms = rooms.remByVal('hello')

console.log(rooms)

I don't know how you are expecting array.remove(int) to behave. There are three possibilities I can think of that you might want.

To remove an element of an array at an index i:

array.splice(i, 1);

If you want to remove every element with value number from the array:

for(var i = array.length - 1; i >= 0; i--) {
    if(array[i] === number) {
        array.splice(i, 1);
    }
}

If you just want to make the element at index i no longer exist, but you don't want the indexes of the other elements to change:

delete array[i];

Find the index of the array element you want to remove using indexOf, and then remove that index with splice.

The splice() method changes the contents of an array by removing existing elements and/or adding new elements.

const array = [2, 5, 9];

console.log(array);

const index = array.indexOf(5);
if (index > -1) {
  array.splice(index, 1);
}

// array = [2, 9]
console.log(array); 

The second parameter of splice is the number of elements to remove. Note that splice modifies the array in place and returns a new array containing the elements that have been removed.


For the reason of completeness, here are functions. First function removes only single occurrence (i.e. removing first match of 5 from [2,5,9,1,5,8,5]), while second function removes all occurrences:

function removeItemOnce(arr, value) { 
    var index = arr.indexOf(value);
    if (index > -1) {
        arr.splice(index, 1);
    }
    return arr;
}

function removeItemAll(arr, value) {
    var i = 0;
    while (i < arr.length) {
        if(arr[i] === value) {
            arr.splice(i, 1);
        } else {
            ++i;
        }
    }
    return arr;
}

It depends on whether you want to keep an empty spot or not.

If you do want an empty slot, delete is fine:

delete array[index];

If you don't, you should use the splice method:

array.splice(index, 1);

And if you need the value of that item, you can just store the returned array's element:

var value = array.splice(index, 1)[0];

In case you want to do it in some order, you can use array.pop() for the last one or array.shift() for the first one (and both return the value of the item too).

And if you don't know the index of the item, you can use array.indexOf(item) to get it (in a if() to get one item or in a while() to get all of them). array.indexOf(item) returns either the index or -1 if not found. 

If you want a new array with the deleted positions removed, you can always delete the specific element and filter out the array. It might need an extension of the array object for browsers that don't implement the filter method, but in the long term it's easier since all you do is this:

var my_array = [1, 2, 3, 4, 5, 6];
delete my_array[4];
console.log(my_array.filter(function(a){return typeof a !== 'undefined';}));

It should display [1, 2, 3, 4, 6].

There are two major approaches:

  1. splice(): anArray.splice(index, 1);

  2. delete: delete anArray[index];

Be careful when you use delete for an array. It is good for deleting attributes of objects, but not so good for arrays. It is better to use splice for arrays.

Keep in mind that when you use delete for an array you could get wrong results for anArray.length. In other words, delete would remove the element, but it wouldn't update the value of length property.

You can also expect to have holes in index numbers after using delete, e.g. you could end up with having indexes 1, 3, 4, 8, 9, and 11 and length as it was before using delete. In that case, all indexed for loops would crash, since indexes are no longer sequential.

If you are forced to use delete for some reason, then you should use for each loops when you need to loop through arrays. As the matter of fact, always avoid using indexed for loops, if possible. That way the code would be more robust and less prone to problems with indexes.

Update: This method is recommended only if you cannot use ECMAScript 2015 (formerly known as ES6). If you can use it, other answers here provide much neater implementations.


This gist here will solve your problem, and also deletes all occurrences of the argument instead of just 1 (or a specified value).

Array.prototype.destroy = function(obj){
    // Return null if no objects were found and removed
    var destroyed = null;

    for(var i = 0; i < this.length; i++){

        // Use while-loop to find adjacent equal objects
        while(this[i] === obj){

            // Remove this[i] and store it within destroyed
            destroyed = this.splice(i, 1)[0];
        }
    }

    return destroyed;
}

Usage:

var x = [1, 2, 3, 3, true, false, undefined, false];

x.destroy(3);         // => 3
x.destroy(false);     // => false
x;                    // => [1, 2, true, undefined]

x.destroy(true);      // => true
x.destroy(undefined); // => undefined
x;                    // => [1, 2]

x.destroy(3);         // => null
x;                    // => [1, 2]

Check out this code. It works in every major browser.

remove_item = function (arr, value) {
    var b = '';
    for (b in arr) {
        if (arr[b] === value) {
            arr.splice(b, 1);
            break;
        }
    }
    return arr;
}

Call this function

remove_item(array,value);

You can iterate over each array-item and splice it if it exist in your array.

function destroy(arr, val) {
    for (var i = 0; i < arr.length; i++) if (arr[i] === val) arr.splice(i, 1);
    return arr;
}

Create new array:

var my_array = new Array();

Add elements to this array:

my_array.push("element1");

The function indexOf (returns index or -1 when not found):

var indexOf = function(needle)
{
    if (typeof Array.prototype.indexOf === 'function') // Newer browsers
    {
        indexOf = Array.prototype.indexOf;
    }
    else // Older browsers
    {
        indexOf = function(needle)
        {
            var index = -1;

            for (var i = 0; i < this.length; i++)
            {
                if (this[i] === needle)
                {
                    index = i;
                    break;
                }
            }
            return index;
        };
    }

    return indexOf.call(this, needle);
};

Check index of this element (tested with Firefox and Internet Explorer 8 (and later)):

var index = indexOf.call(my_array, "element1");

Remove 1 element located at index from the array

my_array.splice(index, 1);

A friend was having issues in Internet Explorer 8 and showed me what he did. I told him it was wrong, and he told me he got the answer here. The current top answer will not work in all browsers (Internet Explorer 8 for example), and it will only remove the first occurrence of the item.

Remove ALL instances from an array

function remove(arr, item) {
    for (var i = arr.length; i--;) {
        if (arr[i] === item) {
            arr.splice(i, 1);
        }
    }
}

It loops through the array backwards (since indices and length will change as items are removed) and removes the item if it's found. It works in all browsers.

You can do a backward loop to make sure not to screw up the indexes, if there are multiple instances of the element.

var myElement = "chocolate";
var myArray = ['chocolate', 'poptart', 'poptart', 'poptart', 'chocolate', 'poptart', 'poptart', 'chocolate'];

/* Important code */
for (var i = myArray.length - 1; i >= 0; i--) {
    if (myArray[i] == myElement) myArray.splice(i, 1);
}

Live Demo

John Resig posted a good implementation:

// Array Remove - By John Resig (MIT Licensed)
Array.prototype.remove = function(from, to) {
  var rest = this.slice((to || from) + 1 || this.length);
  this.length = from < 0 ? this.length + from : from;
  return this.push.apply(this, rest);
};

If you don’t want to extend a global object, you can do something like the following, instead:

// Array Remove - By John Resig (MIT Licensed)
Array.remove = function(array, from, to) {
    var rest = array.slice((to || from) + 1 || array.length);
    array.length = from < 0 ? array.length + from : from;
    return array.push.apply(array, rest);
};

But the main reason I am posting this is to warn users against the alternative implementation suggested in the comments on that page (Dec 14, 2007):

Array.prototype.remove = function(from, to){
  this.splice(from, (to=[0,from||1,++to-from][arguments.length])<0?this.length+to:to);
  return this.length;
};

It seems to work well at first, but through a painful process I discovered it fails when trying to remove the second to last element in an array. For example, if you have a 10-element array and you try to remove the 9th element with this:

myArray.remove(8);

You end up with an 8-element array. Don't know why but I confirmed John's original implementation doesn't have this problem.

There is no need to use indexOf or splice. However, it performs better if you only want to remove one occurrence of an element.

Find and move (move):

function move(arr, val) {
  var j = 0;
  for (var i = 0, l = arr.length; i < l; i++) {
    if (arr[i] !== val) {
      arr[j++] = arr[i];
    }
  }
  arr.length = j;
}

Use indexOf and splice (indexof):

function indexof(arr, val) {
  var i;
  while ((i = arr.indexOf(val)) != -1) {
    arr.splice(i, 1);
  }
}

Use only splice (splice):

function splice(arr, val) {
  for (var i = arr.length; i--;) {
    if (arr[i] === val) {
      arr.splice(i, 1);
    }
  }
}

Run-times on nodejs for array with 1000 elements (average over 10000 runs):

indexof is approximately 10x slower than move. Even if improved by removing the call to indexOf in splice it performs much worse than move.

Remove all occurrences:
    move 0.0048 ms
    indexof 0.0463 ms
    splice 0.0359 ms

Remove first occurrence:
    move_one 0.0041 ms
    indexof_one 0.0021 ms
Array.prototype.removeItem = function(a) {
    for (i = 0; i < this.length; i++) {
        if (this[i] == a) {
            for (i2 = i; i2 < this.length - 1; i2++) {
                this[i2] = this[i2 + 1];
            }
            this.length = this.length - 1
            return;
        }
    }
}

var recentMovies = ['Iron Man', 'Batman', 'Superman', 'Spiderman'];
recentMovies.removeItem('Superman');

I also ran into the situation where I had to remove an element from Array. .indexOf was not working in Internet Explorer, so I am sharing my working jQuery.inArray() solution:

var index = jQuery.inArray(val, arr);
if (index > -1) {
    arr.splice(index, 1);
    //console.log(arr);
}

Edited on 2016 October

  • Do it simple, intuitive and explicit (Occam's razor)
  • Do it immutable (original array stay unchanged)
  • Do it with standard JavaScript functions, if your browser doesn't support them - use polyfill

In this code example I use "array.filter(...)" function to remove unwanted items from an array. This function doesn't change the original array and creates a new one. If your browser doesn't support this function (e.g. Internet Explorer before version 9, or Firefox before version 1.5), consider using the filter polyfill from Mozilla.

Removing item (ECMA-262 Edition 5 code aka oldstyle JavaScript)

var value = 3

var arr = [1, 2, 3, 4, 5, 3]

arr = arr.filter(function(item) {
    return item !== value
})

console.log(arr)
// [ 1, 2, 4, 5 ]

Removing item (ECMAScript 6 code)

let value = 3

let arr = [1, 2, 3, 4, 5, 3]

arr = arr.filter(item => item !== value)

console.log(arr)
// [ 1, 2, 4, 5 ]

IMPORTANT ECMAScript 6 "() => {}" arrow function syntax is not supported in Internet Explorer at all, Chrome before 45 version, Firefox before 22 version, and Safari before 10 version. To use ECMAScript 6 syntax in old browsers you can use BabelJS.


Removing multiple items (ECMAScript 7 code)

An additional advantage of this method is that you can remove multiple items

let forDeletion = [2, 3, 5]

let arr = [1, 2, 3, 4, 5, 3]

arr = arr.filter(item => !forDeletion.includes(item))
// !!! Read below about array.includes(...) support !!!

console.log(arr)
// [ 1, 4 ]

IMPORTANT "array.includes(...)" function is not supported in Internet Explorer at all, Chrome before 47 version, Firefox before 43 version, Safari before 9 version, and Edge before 14 version so here is polyfill from Mozilla.

Removing multiple items (in the future, maybe)

If the "This-Binding Syntax" proposal is ever accepted, you'll be able to do this:

// array-lib.js

export function remove(...forDeletion) {
    return this.filter(item => !forDeletion.includes(item))
}

// main.js

import { remove } from './array-lib.js'

let arr = [1, 2, 3, 4, 5, 3]

// :: This-Binding Syntax Proposal
// using "remove" function as "virtual method"
// without extending Array.prototype
arr = arr::remove(2, 3, 5)

console.log(arr)
// [ 1, 4 ]

Try it yourself in BabelJS :)

Reference

I'm pretty new to JavaScript and needed this functionality. I merely wrote this:

function removeFromArray(array, item, index) {
  while((index = array.indexOf(item)) > -1) {
    array.splice(index, 1);
  }
}

Then when I want to use it:

//Set-up some dummy data
var dummyObj = {name:"meow"};
var dummyArray = [dummyObj, "item1", "item1", "item2"];

//Remove the dummy data
removeFromArray(dummyArray, dummyObj);
removeFromArray(dummyArray, "item2");

Output - As expected. ["item1", "item1"]

You may have different needs than I, so you can easily modify it to suit them. I hope this helps someone.

Based on all the answers which were mainly correct and taking into account the best practices suggested (especially not using Array.prototype directly), I came up with the below code:

function arrayWithout(arr, values) {
  var isArray = function(canBeArray) {
    if (Array.isArray) {
      return Array.isArray(canBeArray);
    }
    return Object.prototype.toString.call(canBeArray) === '[object Array]';
  };

  var excludedValues = (isArray(values)) ? values : [].slice.call(arguments, 1);
  var arrCopy = arr.slice(0);

  for (var i = arrCopy.length - 1; i >= 0; i--) {
    if (excludedValues.indexOf(arrCopy[i]) > -1) {
      arrCopy.splice(i, 1);
    }
  }

  return arrCopy;
}

Reviewing the above function, despite the fact that it works fine, I realised there could be some performance improvement. Also using ES6 instead of ES5 is a much better approach. To that end, this is the improved code:

const arrayWithoutFastest = (() => {
  const isArray = canBeArray => ('isArray' in Array) 
    ? Array.isArray(canBeArray) 
    : Object.prototype.toString.call(canBeArray) === '[object Array]';

  let mapIncludes = (map, key) => map.has(key);
  let objectIncludes = (obj, key) => key in obj;
  let includes;

  function arrayWithoutFastest(arr, ...thisArgs) {
    let withoutValues = isArray(thisArgs[0]) ? thisArgs[0] : thisArgs;

    if (typeof Map !== 'undefined') {
      withoutValues = withoutValues.reduce((map, value) => map.set(value, value), new Map());
      includes = mapIncludes;
    } else {
      withoutValues = withoutValues.reduce((map, value) => { map[value] = value; return map; } , {}); 
      includes = objectIncludes;
    }

    const arrCopy = [];
    const length = arr.length;

    for (let i = 0; i < length; i++) {
      // If value is not in exclude list
      if (!includes(withoutValues, arr[i])) {
        arrCopy.push(arr[i]);
      }
    }

    return arrCopy;
  }

  return arrayWithoutFastest;  
})();

How to use:

const arr = [1,2,3,4,5,"name", false];

arrayWithoutFastest(arr, 1); // will return array [2,3,4,5,"name", false]
arrayWithoutFastest(arr, 'name'); // will return [2,3,4,5, false]
arrayWithoutFastest(arr, false); // will return [2,3,4,5]
arrayWithoutFastest(arr,[1,2]); // will return [3,4,5,"name", false];
arrayWithoutFastest(arr, {bar: "foo"}); // will return the same array (new copy)

I am currently writing a blog post in which I have benchmarked several solutions for Array without problem and compared the time it takes to run. I will update this answer with the link once I finish that post. Just to let you know, I have compared the above against lodash's without and in case the browser supports Map, it beats lodash! Notice that I am not using Array.prototype.indexOf or Array.prototype.includes as wrapping the exlcudeValues in a Map or Object makes querying faster!

In CoffeeScript:

my_array.splice(idx, 1) for ele, idx in my_array when ele is this_value

I know there are a lot of answers already, but many of them seem to over complicate the problem. Here is a simple, recursive way of removing all instances of a key - calls self until index isn't found. Yes, it only works in browsers with indexOf, but it's simple and can be easily polyfilled.

Stand-alone function

function removeAll(array, key){
    var index = array.indexOf(key);

    if(index === -1) return;

    array.splice(index, 1);
    removeAll(array,key);
}

Prototype method

Array.prototype.removeAll = function(key){
    var index = this.indexOf(key);

    if(index === -1) return;

    this.splice(index, 1);
    this.removeAll(key);
}

You can do it easily with the filter method:

function remove(arrOriginal, elementToRemove){
    return arrOriginal.filter(function(el){return el !== elementToRemove});
}
console.log(remove([1, 2, 1, 0, 3, 1, 4], 1));

This removes all elements from the array and also works faster than a combination of slice and indexOf.

I like this version of splice, removing an element by its value using $.inArray:

$(document).ready(function(){
    var arr = ["C#","Ruby","PHP","C","C++"];
    var itemtoRemove = "PHP";
    arr.splice($.inArray(itemtoRemove, arr),1);
});

This provides a predicate instead of a value.

NOTE: it will update the given array, and return the affected rows.

Usage

var removed = helper.removeOne(arr, row => row.id === 5 );

var removed = helper.remove(arr, row => row.name.startsWith('BMW'));

Definition

var helper = {

    // Remove and return the first occurrence

    removeOne: function(array, predicate) {
        for (var i = 0; i < array.length; i++) {
            if (predicate(array[i])) {
                return array.splice(i, 1);
            }
        }
    },

    // Remove and return all occurrences

    remove: function(array, predicate) {
        var removed = [];

        for (var i = 0; i < array.length;) {

            if (predicate(array[i])) {
                removed.push(array.splice(i, 1));
                continue;
            }
            i++;
        }
        return removed;
    }
};

Underscore.js can be used to solve issues with multiple browsers. It uses in-build browser methods if present. If they are absent like in the case of older Internet Explorer versions it uses its own custom methods.

A simple example to remove elements from array (from the website):

_.without([1, 2, 1, 0, 3, 1, 4], 0, 1); // => [2, 3, 4]
var index,
    input = [1,2,3],
    indexToRemove = 1;
    integers = [];

for (index in input) {
    if (input.hasOwnProperty(index)) {
        if (index !== indexToRemove) {
            integers.push(result); 
        }
    }
}
input = integers;

This solution will take an array of input and will search through the input for the value to remove. This will loop through the entire input array and the result will be a second array integers that has had the specific index removed. The integers array is then copied back into the input array.

Use jQuery's InArray:

A = [1, 2, 3, 4, 5, 6];
A.splice($.inArray(3, A), 1);
//It will return A=[1, 2, 4, 5, 6]`   

Note: inArray will return -1, if the element was not found.

Removing the value with index and splice!

function removeArrValue(arr,value) {
    var index = arr.indexOf(value);
    if (index > -1) {
        arr.splice(index, 1);
    }
    return arr;
}

If you must support older versions of Internet Explorer, I recommend using the following polyfill (note: this is not a framework). It's a 100% backwards-compatible replacement of all modern array methods (JavaScript 1.8.5 / ECMAScript 5 Array Extras) that works for Internet Explorer 6+, Firefox 1.5+, Chrome, Safari, & Opera.

https://github.com/plusdude/array-generics

There are many fantastic answers here, but for me, what worked most simply wasn't removing my element from the array completely, but simply setting the value of it to null.

This works for most cases I have and is a good solution since I will be using the variable later and don't want it gone, just empty for now. Also, this approach is completely cross-browser compatible.

array.key = null;

If you have complex objects in the array you can use filters? In situations where $.inArray or array.splice is not as easy to use. Especially if the objects are perhaps shallow in the array.

E.g. if you have an object with an Id field and you want the object removed from an array:

this.array = this.array.filter(function(element, i) {
    return element.id !== idToRemove;
});

You can use lodash _.pull (mutate array), _.pullAt (mutate array) or _.without (does't mutate array),

var array1 = ['a', 'b', 'c', 'd']
_.pull(array1, 'c')
console.log(array1) // ['a', 'b', 'd']

var array2 = ['e', 'f', 'g', 'h']
_.pullAt(array2, 0)
console.log(array2) // ['f', 'g', 'h']

var array3 = ['i', 'j', 'k', 'l']
var newArray = _.without(array3, 'i') // ['j', 'k', 'l']
console.log(array3) // ['i', 'j', 'k', 'l']

The following method will remove all entries of a given value from an array without creating a new array and with only one iteration which is superfast. And it works in ancient Internet Explorer 5.5 browser:

function removeFromArray(arr, removeValue) {
  for (var i = 0, k = 0, len = arr.length >>> 0; i < len; i++) {
    if (k > 0)
      arr[i - k] = arr[i];

    if (arr[i] === removeValue)
      k++;
  }

  for (; k--;)
    arr.pop();
}

var a = [0, 1, 0, 2, 0, 3];

document.getElementById('code').innerHTML =
  'Initial array [' + a.join(', ') + ']';
//Initial array [0, 1, 0, 2, 0, 3]

removeFromArray(a, 0);

document.getElementById('code').innerHTML +=
  '<br>Resulting array [' + a.join(', ') + ']';
//Resulting array [1, 2, 3]
<code id="code"></code>

Remove last occurrence or all occurrences, or first occurrence?

var array = [2, 5, 9, 5];

// Remove last occurrence (or all occurrences)
for (var i = array.length; i--;) {
  if (array[i] === 5) {
     array.splice(i, 1);
     break; // Remove this line to remove all occurrences
  }
}

or

var array = [2, 5, 9, 5];

// Remove first occurrence
for (var i = 0; array.length; i++) {
  if (array[i] === 5) {
     array.splice(i, 1);
     break; // Do not remove this line
  }
}

By my solution you can remove one or more than one item in an array thanks to pure JavaScript. There is no need for another JavaScript library.

var myArray = [1,2,3,4,5]; // First array

var removeItem = function(array,value) {  // My clear function
    if(Array.isArray(value)) {  // For multi remove
        for(var i = array.length - 1; i >= 0; i--) {
            for(var j = value.length - 1; j >= 0; j--) {
                if(array[i] === value[j]) {
                    array.splice(i, 1);
                };
            }
        }
    }
    else { // For single remove
        for(var i = array.length - 1; i >= 0; i--) {
            if(array[i] === value) {
                array.splice(i, 1);
            }
        }
    }
}

removeItem(myArray,[1,4]); // myArray will be [2,3,5]

Vanilla JavaScript (ES5.1) – in place edition

Browser support: Internet Explorer 9 or later (detailed browser support)

/**
 * Removes all occurences of the item from the array.
 *
 * Modifies the array “in place”, i.e. the array passed as an argument
 * is modified as opposed to creating a new array. Also returns the modified
 * array for your convenience.
 */
function removeInPlace(array, item) {
    var foundIndex, fromIndex;

    // Look for the item (the item can have multiple indices)
    fromIndex = array.length - 1;
    foundIndex = array.lastIndexOf(item, fromIndex);

    while (foundIndex !== -1) {
        // Remove the item (in place)
        array.splice(foundIndex, 1);

        // Bookkeeping
        fromIndex = foundIndex - 1;
        foundIndex = array.lastIndexOf(item, fromIndex);
    }

    // Return the modified array
    return array;
}

Vanilla JavaScript (ES5.1) – immutable edition

Browser support: Same as vanilla JavaScript in place edition

/**
 * Removes all occurences of the item from the array.
 *
 * Returns a new array with all the items of the original array except
 * the specified item.
 */
function remove(array, item) {
    var arrayCopy;

    arrayCopy = array.slice();

    return removeInPlace(arrayCopy, item);
}

Vanilla ES6 – immutable edition

Browser support: Chrome 46, Edge 12, Firefox 16, Opera 37, Safari 8 (detailed browser support)

/**
 * Removes all occurences of the item from the array.
 *
 * Returns a new array with all the items of the original array except
 * the specified item.
 */
function remove(array, item) {
    // Copy the array
    array = [...array];

    // Look for the item (the item can have multiple indices)
    let fromIndex = array.length - 1;
    let foundIndex = array.lastIndexOf(item, fromIndex);

    while (foundIndex !== -1) {
        // Remove the item by generating a new array without it
        array = [
            ...array.slice(0, foundIndex),
            ...array.slice(foundIndex + 1),
        ];

        // Bookkeeping
        fromIndex = foundIndex - 1;
        foundIndex = array.lastIndexOf(item, fromIndex)
    }

    // Return the new array
    return array;
}

A more modern, ECMAScript 2015 (formerly known as Harmony or ES 6) approach. Given:

const items = [1, 2, 3, 4];
const index = 2;

Then:

items.filter((x, i) => i !== index);

Yielding:

[1, 2, 4]

You can use Babel and a polyfill service to ensure this is well supported across browsers.

I think many of the JavaScript instructions are not well thought out for functional programming. Splice returns the deleted element where most of the time you need the reduced array. This is bad.

Imagine you are doing a recursive call and have to pass an array with one less item, probably without the current indexed item. Or imagine you are doing another recursive call and has to pass an array with an element pushed.

In neither of these cases you can do myRecursiveFunction(myArr.push(c)) or myRecursiveFunction(myArr.splice(i,1)). The first idiot will in fact pass the length of the array and the second idiot will pass the deleted element as a parameter.

So what I do in fact... For deleting an array element and passing the resulting to a function as a parameter at the same time I do as follows

myRecursiveFunction(myArr.slice(0,i).concat(a.slice(i+1)))

When it comes to push that's more silly... I do like,

myRecursiveFunction((myArr.push(c),myArr))

I believe in a proper functional language a method mutating the object it's called upon must return a reference to the very object as a result.

Array.prototype.remove = function(x) {
    var y=this.slice(x+1);
    var z=[];
    for(i=0;i<=x-1;i++) {
        z[z.length] = this[i];
    }

    for(i=0;i<y.length;i++){
        z[z.length]=y[i];
    }

    return z;
}

Use jQuery.grep():

var y = [1, 2, 3, 9, 4]
var removeItem = 9;

y = jQuery.grep(y, function(value) {
  return value != removeItem;
});
console.log(y)
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.2/jquery.min.js"></script>

I made a fairly efficient extension to the base JavaScript array:

Array.prototype.drop = function(k) {
  var valueIndex = this.indexOf(k);
  while(valueIndex > -1) {
    this.removeAt(valueIndex);
    valueIndex = this.indexOf(k);
  }
};

You can use ES6. For example to delete the value '3' in this case:

var array=['1','2','3','4','5','6']
var newArray = array.filter((value)=>value!='3');
console.log(newArray);

Output :

["1", "2", "4", "5", "6"]

ES6 & without mutation: (October 2016)

const removeByIndex = (list, index) =>
      [
        ...list.slice(0, index),
        ...list.slice(index + 1)
      ];
         
output = removeByIndex([33,22,11,44],1) //=> [33,11,44]
      
console.log(output)

While most of the previous answers answer the question, it is not clear enough why the slice() method has not been used. Yes, filter() meets the immutability criteria, but how about doing the following shorter equivalent?

const myArray = [1,2,3,4];

And now let’s say that we should remove the second element from the array, we can simply do:

const newArray = myArray.slice(0, 1).concat(myArray.slice(2, 4));

// [1,3,4]

This way of deleting an element from an array is strongly encouraged today in the community due to its simple and immutable nature. In general, methods which cause mutation should be avoided. For example, you are encouraged to replace push() with concat() and splice() with slice().

I made a function:

function pop(valuetoremove, myarray) {
    var indexofmyvalue = myarray.indexOf(valuetoremove);
    myarray.splice(indexofmyvalue, 1);
}

And used it like this:

pop(valuetoremove, myarray);

Remove one value, using loose comparison, without mutating the original array, ES6

/**
 * Removes one instance of `value` from `array`, without mutating the original array. Uses loose comparison.
 *
 * @param {Array} array Array to remove value from
 * @param {*} value Value to remove
 * @returns {Array} Array with `value` removed
 */
export function arrayRemove(array, value) {
    for(let i=0; i<array.length; ++i) {
        if(array[i] == value) {
            let copy = [...array];
            copy.splice(i, 1);
            return copy;
        }
    }
    return array;
}

Remove element at index i, without mutating the original array:

/**
* removeElement
* @param {Array} array
* @param {Number} index
*/
function removeElement(array, index) {
   return Array.from(array).splice(index, 1);
}

// Another way is
function removeElement(array, index) {
   return array.slice(0).splice(index, 1);
}

2017-05-08

Most of the given answers work for strict comparison, meaning that both objects reference the exact same object in memory (or are primitive types), but often you want to remove a non-primitive object from an array that has a certain value. For instance, if you make a call to a server and want to check a retrieved object against a local object.

const a = {'field': 2} // Non-primitive object
const b = {'field': 2} // Non-primitive object with same value
const c = a            // Non-primitive object that reference the same object as "a"

assert(a !== b) // Don't reference the same item, but have same value
assert(a === c) // Do reference the same item, and have same value (naturally)

//Note: there are many alternative implementations for valuesAreEqual
function valuesAreEqual (x, y) {
   return  JSON.stringify(x) === JSON.stringify(y)
}


//filter will delete false values
//Thus, we want to return "false" if the item
// we want to delete is equal to the item in the array
function removeFromArray(arr, toDelete){
    return arr.filter(target => {return !valuesAreEqual(toDelete, target)})
}

const exampleArray = [a, b, b, c, a, {'field': 2}, {'field': 90}];
const resultArray = removeFromArray(exampleArray, a);

//resultArray = [{'field':90}]

There are alternative/faster implementations for valuesAreEqual, but this does the job. You can also use a custom comparator if you have a specific field to check (for example, some retrieved UUID vs a local UUID).

Also note that this is a functional operation, meaning that it does not mutate the original array.

OK, for example you have the array below:

var num = [1, 2, 3, 4, 5];

And we want to delete number 4. You can simply use the below code:

num.splice(num.indexOf(4), 1); // num will be [1, 2, 3, 5];

If you are reusing this function, you write a reusable function which will be attached to the native array function like below:

Array.prototype.remove = Array.prototype.remove || function(x) {
  const i = this.indexOf(x);
  if(i===-1)
      return;
  this.splice(i, 1); // num.remove(5) === [1, 2, 3];
}

But how about if you have the below array instead with a few [5]s in the array?

var num = [5, 6, 5, 4, 5, 1, 5];

We need a loop to check them all, but an easier and more efficient way is using built-in JavaScript functions, so we write a function which use a filter like below instead:

const _removeValue = (arr, x) => arr.filter(n => n!==x);
//_removeValue([1, 2, 3, 4, 5, 5, 6, 5], 5) // Return [1, 2, 3, 4, 6]

Also there are third-party libraries which do help you to do this, like Lodash or Underscore. For more information, look at lodash _.pull, _.pullAt or _.without.

Remove by Index

A function that returns a copy of array without the element at index:

/**
* removeByIndex
* @param {Array} array
* @param {Number} index
*/
function removeByIndex(array, index){
      return array.filter(function(elem, _index){
          return index != _index;
    });
}
l = [1,3,4,5,6,7];
console.log(removeByIndex(l, 1));

$> [ 1, 4, 5, 6, 7 ]

Remove by Value

Function that return a copy of array without the Value.

/**
* removeByValue
* @param {Array} array
* @param {Number} value
*/
function removeByValue(array, value){
      return array.filter(function(elem, _index){
          return value != elem;
    });
}
l = [1,3,4,5,6,7];
console.log(removeByValue(l, 5));

$> [ 1, 3, 4, 6, 7]

There are already a lot of answers, but because no one has done it with a one liner yet, I figured I'd show my method. It takes advantage of the fact that the string.split() function will remove all of the specified characters when creating an array. Here is an example:

var ary = [1,2,3,4,1234,10,4,5,7,3];
out = ary.join("-").split("-4-").join("-").split("-");
console.log(out);

In this example, all of the 4's are being removed from the array ary. However, it is important to note that any array containing the character "-" will cause issues with this example. In short, it will cause the join("-") function to piece your string together improperly. In such a situation, all of the the "-" strings in the above snipet can be replaced with any string that will not be used in the original array. Here is another example:

var ary = [1,2,3,4,'-',1234,10,'-',4,5,7,3];
out = ary.join("[email protected]#").split("[email protected]#[email protected]#").join("[email protected]#").split("[email protected]#");
console.log(out);

I post my code that removes an array element in place, and reduce the array length as well.

function removeElement(idx, arr) {
    // Check the index value
    if (idx < 0 || idx >= arr.length) {
        return;
    }
    // Shift the elements
    for (var i = idx; i > 0; --i) {
        arr[i] = arr[i - 1];
    }
    // Remove the first element in array
    arr.shift();
}

For anyone looking to replicate a method that will return a new array that has duplicate numbers or strings removed, this has been put together from existing answers:

function uniq(array) {
  var len = array.length;
  var dupFree = [];
  var tempObj = {};

  for (var i = 0; i < len; i++) {
    tempObj[array[i]] = 0;
  }

  console.log(tempObj);

  for (var i in tempObj) {
    var element = i;
    if (i.match(/\d/)) {
      element = Number(i);
    }
    dupFree.push(element);
  }

  return dupFree;
}

What a shame you have an array of integers, not an object where the keys are string equivalents of these integers.

I've looked through a lot of these answers and they all seem to use "brute force" as far as I can see. I haven't examined every single one, apologies if this is not so. For a smallish array this is fine, but what if you have 000s of integers in it?

Correct me if I'm wrong, but can't we assume that in a key => value map, of the kind which a JavaScript object is, that the key retrieval mechanism can be assumed to be highly engineered and optimised? (NB: if some super-expert tells me that this is not the case, I can suggest using ECMAScript 6's Map class instead, which certainly will be).

I'm just suggesting that, in certain circumstances, the best solution might be to convert your array to an object... the problem being, of course, that you might have repeating integer values. I suggest putting those in buckets as the "value" part of the key => value entries. (NB: if you are sure you don't have any repeating array elements this can be much simpler: values "same as" keys, and just go Object.values(...) to get back your modified array).

So you could do:

const arr = [ 1, 2, 55, 3, 2, 4, 55 ];
const f =    function( acc, val, currIndex ){
    // We have not seen this value before: make a bucket... NB: although val's typeof is 'number',
    // there is seamless equivalence between the object key (always string)
    // and this variable val.
    ! ( val in acc ) ? acc[ val ] = []: 0;
    // Drop another array index in the bucket
    acc[ val ].push( currIndex );
    return acc;
}
const myIntsMapObj = arr.reduce( f, {});

console.log( myIntsMapObj );

Output:

Object [ <1 empty slot>, Array1, Array[2], Array1, Array1, <5 empty slots>, 46 more… ]

It is then easy to delete all the numbers 55.

delete myIntsMapObj[ 55 ]; // Again, although keys are strings this works

You don't have to delete them all: index values are pushed into their buckets in order of appearance, so (for example):

myIntsMapObj[ 55 ].shift(); // And
myIntsMapObj[ 55 ].pop();

will delete the first and last occurrence respectively. You can count frequency of occurrence easily, replace all 55s with 3s by transferring the contents of one bucket to another, etc.

Retrieving a modified int array from your "bucket object" is slightly involved but not so much: each bucket contains the index (in the original array) of the value represented by the (string) key. Each of these bucket values is also unique (each is the unique index value in the original array): so you turn them into keys in a new object, with the (real) integer from the "integer string key" as value... then sort the keys and go Object.values( ... ).

This sounds very involved and time-consuming... but obviously everything depends on the circumstances and desired usage. My understanding is that all versions and contexts of JavaScript operate only in one thread, and the thread doesn't "let go", so there could be some horrible congestion with a "brute force" method: caused not so much by the indexOf ops, but multiple repeated slice/splice ops.

Addendum If you're sure this is too much engineering for your use case surely the simplest "brute force" approach is

const arr = [ 1, 2, 3, 66, 8, 2, 3, 2 ];
const newArray = arr.filter( number => number !== 3 );
console.log( newArray )

(Yes, other answers have spotted Array.prototype.filter...)

You should never mutate your array. As this is against the functional programming pattern. You can create a new array without referencing the array you want to change data of using the ECMAScript 6 method filter;

var myArray = [1, 2, 3, 4, 5, 6];

Suppose you want to remove 5 from the array, you can simply do it like this:

myArray = myArray.filter(value => value !== 5);

This will give you a new array without the value you wanted to remove. So the result will be:

 [1, 2, 3, 4, 6]; // 5 has been removed from this array

For further understanding you can read the MDN documentation on Array.filter.

var array = [2, 5, 9];
array.splice(array.findIndex(x => x==5), 1);

Using Array.findindex, we can reduce the number of lines of code.

developer.mozilla.org

I just created a polyfill on the Array.prototype via Object.defineProperty to remove a desired element in an array without leading to errors when iterating over it later via for .. in ..

if (!Array.prototype.remove) {
  // Object.definedProperty is used here to avoid problems when iterating with "for .. in .." in Arrays
  // https://stackoverflow.com/questions/948358/adding-custom-functions-into-array-prototype
  Object.defineProperty(Array.prototype, 'remove', {
    value: function () {
      if (this == null) {
        throw new TypeError('Array.prototype.remove called on null or undefined')
      }

      for (var i = 0; i < arguments.length; i++) {
        if (typeof arguments[i] === 'object') {
          if (Object.keys(arguments[i]).length > 1) {
            throw new Error('This method does not support more than one key:value pair per object on the arguments')
          }
          var keyToCompare = Object.keys(arguments[i])[0]

          for (var j = 0; j < this.length; j++) {
            if (this[j][keyToCompare] === arguments[i][keyToCompare]) {
              this.splice(j, 1)
              break
            }
          }
        } else {
          var index = this.indexOf(arguments[i])
          if (index !== -1) {
            this.splice(index, 1)
          }
        }
      }
      return this
    }
  })
} else {
  var errorMessage = 'DANGER ALERT! Array.prototype.remove has already been defined on this browser. '
  errorMessage += 'This may lead to unwanted results when remove() is executed.'
  console.log(errorMessage)
}

Removing an integer value

var a = [1, 2, 3]
a.remove(2)
a // Output => [1, 3]

Removing a string value

var a = ['a', 'ab', 'abc']
a.remove('abc')
a // Output => ['a', 'ab']

Removing a boolean value

var a = [true, false, true]
a.remove(false)
a // Output => [true, true]

It is also possible to remove an object inside the array via this Array.prototype.remove method. You just need to specify the key => value of the Object you want to remove.

Removing an object value

var a = [{a: 1, b: 2}, {a: 2, b: 2}, {a: 3, b: 2}]
a.remove({a: 1})
a // Output => [{a: 2, b: 2}, {a: 3, b: 2}]

A very naive implementation would be as follows:

Array.prototype.remove = function(data) {
    const dataIdx = this.indexOf(data)
    if(dataIdx >= 0) {
        this.splice(dataIdx ,1);
    }
    return this.length;
}

let a = [1,2,3];
// This will change arr a to [1, 3]
a.remove(2);

I return the length of the array from the function to comply with the other methods, like Array.prototype.push().

let array = [5,5,4,4,2,3,4]    
let newArray = array.join(',').replace('5','').split(',')

This example works if you want to remove one current item.

Your question did not indicate if order or distinct values are a requirement.

If you don't care about order, and will not have the same value in the container more than once, use a Set. It will be way faster, and more succinct.

var aSet = new Set();

aSet.add(1);
aSet.add(2);
aSet.add(3);

aSet.delete(2);

Here are a few ways to remove an item from an array using JavaScript.

All the method described do not mutate the original array, and instead create a new one.

If you know the index of an item

Suppose you have an array, and you want to remove an item in position i.

One method is to use slice():

const items = ['a', 'b', 'c', 'd', 'e', 'f']
const i = 3
const filteredItems = items.slice(0, i).concat(items.slice(i+1, items.length))

console.log(filteredItems)

slice() creates a new array with the indexes it receives. We simply create a new array, from start to the index we want to remove, and concatenate another array from the first position following the one we removed to the end of the array.

If you know the value

In this case, one good option is to use filter(), which offers a more declarative approach:

const items = ['a', 'b', 'c', 'd', 'e', 'f']
const valueToRemove = 'c'
const filteredItems = items.filter(item => item !== valueToRemove)

console.log(filteredItems)

This uses the ES6 arrow functions. You can use the traditional functions to support older browsers:

const items = ['a', 'b', 'c', 'd', 'e', 'f']
const valueToRemove = 'c'
const filteredItems = items.filter(function(item) {
  return item !== valueToRemove
})

console.log(filteredItems)

or you can use Babel and transpile the ES6 code back to ES5 to make it more digestible to old browsers, yet write modern JavaScript in your code.

Removing multiple items

What if instead of a single item, you want to remove many items?

Let's find the simplest solution.

By index

You can just create a function and remove items in series:

const items = ['a', 'b', 'c', 'd', 'e', 'f']

const removeItem = (items, i) =>
  items.slice(0, i-1).concat(items.slice(i, items.length))

let filteredItems = removeItem(items, 3)
filteredItems = removeItem(filteredItems, 5)
//["a", "b", "c", "d"]

console.log(filteredItems)

By value

You can search for inclusion inside the callback function:

const items = ['a', 'b', 'c', 'd', 'e', 'f']
const valuesToRemove = ['c', 'd']
const filteredItems = items.filter(item => !valuesToRemove.includes(item))
// ["a", "b", "e", "f"]

console.log(filteredItems)

Avoid mutating the original array

splice() (not to be confused with slice()) mutates the original array, and should be avoided.

(originally posted at https://flaviocopes.com/how-to-remove-item-from-array/)

Define a method named remove() on array objects using the prototyping feature of JavaScript.

Use splice() method to fulfill your requirement.

Please have a look at the below code.

Array.prototype.remove = function(item) {
    // 'index' will have -1 if 'item' does not exist,
    // else it will have the index of the first item found in the array
    var index = this.indexOf(item);

    if (index > -1) {
        // The splice() method is used to add/remove items(s) in the array
        this.splice(index, 1);
    }
    return index;
}

var arr = [ 11, 22, 67, 45, 61, 89, 34, 12, 7, 8, 3, -1, -4];

// Printing array
// [ 11, 22, 67, 45, 61, 89, 34, 12, 7, 8, 3, -1, -4];
console.log(arr)

// Removing 67 (getting its index, i.e. 2)
console.log("Removing 67")
var index = arr.remove(67)

if (index > 0){
    console.log("Item 67 found at ", index)
} else {
    console.log("Item 67 does not exist in array")
}

// Printing updated array
// [ 11, 22, 45, 61, 89, 34, 12, 7, 8, 3, -1, -4];
console.log(arr)

// ............... Output ................................
// [ 11, 22, 67, 45, 61, 89, 34, 12, 7, 8, 3, -1, -4 ]
// Removing 67
// Item 67 found at  2
// [ 11, 22, 45, 61, 89, 34, 12, 7, 8, 3, -1, -4 ]

Note: The below is the full example code executed on the Node.js REPL which describes the use of push(), pop(), shift(), unshift(), and splice() methods.

> // Defining an array
undefined
> var arr = [12, 45, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34];
undefined
> // Getting length of array
undefined
> arr.length;
16
> // Adding 1 more item at the end i.e. pushing an item
undefined
> arr.push(55);
17
> arr
[ 12, 45, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34, 55 ]
> // Popping item from array (i.e. from end)
undefined
> arr.pop()
55
> arr
[ 12, 45, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
> // Remove item from beginning
undefined
> arr.shift()
12
> arr
[ 45, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
> // Add item(s) at beginning
undefined
> arr.unshift(67); // Add 67 at beginning of the array and return number of items in updated/new array
16
> arr
[ 67, 45, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
> arr.unshift(11, 22); // Adding 2 more items at the beginning of array
18
> arr
[ 11, 22, 67, 45, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
>
> // Define a method on array (temporarily) to remove an item and return the index of removed item; if it is found else return -1
undefined
> Array.prototype.remove = function(item) {
... var index = this.indexOf(item);
... if (index > -1) {
..... this.splice(index, 1); // splice() method is used to add/remove items in array
..... }
... return index;
... }
[Function]
>
> arr
[ 11, 22, 67, 45, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
>
> arr.remove(45);    // Remove 45 (you will get the index of removed item)
3
> arr
[ 11, 22, 67, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
>
> arr.remove(22)    // Remove 22
1
> arr
[ 11, 67, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
> arr.remove(67)    // Remove 67
1
> arr
[ 11, 67, 89, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
>
> arr.remove(89)    // Remove 89
2
> arr
[ 11, 67, 34, 12, 7, 8, 3, -1, -4, -11, 0, 56, 12, 34 ]
>
> arr.remove(100);  // 100 doesn't exist, remove() will return -1
-1
>

I have another good solution for removing from an array:

var words = ['spray', 'limit', 'elite', 'exuberant', 'destruction', 'present'];

const result = words.filter(word => word.length > 6);

console.log(result);
// expected output: Array ["exuberant", "destruction", "present"]

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter

Delete an element from last

arrName.pop();

Delete an element from first

arrName.shift();

Delete from the middle

arrName.splice(starting index, number of element you wnt to delete);

Example: arrName.splice(1, 1);

Delete one element from last

arrName.splice(-1);

Delete by using an array index number

 delete arrName[1];
    Array.prototype.remove = function(start, end) {
        var n = this.slice((end || start) + 1 || this.length);
        return this.length = start < 0 ? this.length + start : start,
        this.push.apply(this, n)
    }

start and end can be negative. In that case they count from the end of the array.

If only start is specified, only one element is removed.

The function returns the new array length.

z = [0,1,2,3,4,5,6,7,8,9];

newlength = z.remove(2,6);

(8) [0, 1, 7, 8, 9]

z=[0,1,2,3,4,5,6,7,8,9];

newlength = z.remove(-4,-2);

(7) [0, 1, 2, 3, 4, 5, 9]

z=[0,1,2,3,4,5,6,7,8,9];

newlength = z.remove(3,-2);

(4) [0, 1, 2, 9]

You have 1 to 9 in the array, and you want remove 5. Use the below code:

var numberArray = [1, 2, 3, 4, 5, 6, 7, 8, 9];

var newNumberArray = numberArray.filter(m => {
  return m !== 5;
});

console.log("new Array, 5 removed", newNumberArray);


If you want to multiple values. Example:- 1,7,8

var numberArray = [1, 2, 3, 4, 5, 6, 7, 8, 9];

var newNumberArray = numberArray.filter(m => {
  return (m !== 1) && (m !== 7) && (m !== 8);
});

console.log("new Array, 1,7 and 8 removed", newNumberArray);


If you want to remove an array value in an array. Example: [3,4,5]

var numberArray = [1, 2, 3, 4, 5, 6, 7, 8, 9];
var removebleArray = [3,4,5];

var newNumberArray = numberArray.filter(m => {
    return !removebleArray.includes(m);
});

console.log("new Array, [3,4,5] removed", newNumberArray);

Includes supported browser is link.

I had this problem myself (in a situation where replacing the array was acceptable) and solved it with a simple:

var filteredItems = this.items.filter(function (i) {
    return i !== item;
});

To give the above snippet a bit of context:

self.thingWithItems = {
    items: [],
    removeItem: function (item) {
        var filteredItems = this.items.filter(function (i) {
            return i !== item;
        });

        this.items = filteredItems;
    }
};

This solution should work with both reference and value items. It all depends whether you need to maintain a reference to the original array as to whether this solution is applicable.

I want to answer based on ECMAScript 6. Assume, you have an array like below:

let arr = [1,2,3,4];

If you want to delete at a special index like 2, write the below code:

arr.splice(2, 1); //=> arr became [1,2,4]

But if you want to delete a special item like 3 and you don't know its index, do like below:

arr = arr.filter(e => e !== 3); //=> arr became [1,2,4]

Hint: please use an arrow function for filter callback unless you will get an empty array.

To me the simpler is the better, and as we are in 2018 (near 2019) I give you this (near) one-liner to answer the original question:

Array.prototype.remove = function (value) {
    return this.filter(f => f != value)
}

The useful thing is that you can use it in a curry expression such as:

[1,2,3].remove(2).sort()
var arr =[1,2,3,4,5];

arr.splice(0,1)

console.log(arr)

Output [2, 3, 4, 5];

Removing a particular element/string from an array can be done in a one-liner:

theArray.splice(theArray.indexOf("stringToRemoveFromArray"), 1);

where:

theArray : the array you want to remove something particular from

stringToRemoveFromArray : the string you want removed and 1 is the amount of elements you want to remove.

NOTE : If "stringToRemoveFromArray" is not located your in array, this will remove last element of array.

Its always good practice to check if the element exists in your array first, before removing it.

if (theArray.indexOf("stringToRemoveFromArray") >= 0){
   theArray.splice(theArray.indexOf("stringToRemoveFromArray"), 1);
}

If you have access to newer Ecmascript versions on your client's computers (WARNING, may not work on older stations):

var array=['1','2','3','4','5','6']
var newArray = array.filter((value)=>value!='3');

Where '3' is the value you want removed from the array. The array would then become : ['1','2','4','5','6']

To remove a particular element or subsequent elements, Array.splice() method works well.

The splice() method changes the contents of an array by removing or replacing existing elements and/or adding new elements, and it returns the removed item(s).

Syntax: array.splice(index, deleteCount, item1, ....., itemX)

Here index is mandatory and rest arguments are optional.

For example:

let arr = [1, 2, 3, 4, 5, 6];
arr.splice(2,1);
console.log(arr);
// [1, 2, 4, 5, 6]

Note: Array.splice() method can be used if you know the index of the element which you want to delete. But we may have a few more cases as mentioned below:

  1. In case you want to delete just last element, you can use Array.pop()

  2. In case you want to delete just first element, you can use Array.shift()

  3. If you know the element alone, but not the position (or index) of the element, and want to delete all matching elements using Array.filter() method:

    let arr = [1, 2, 1, 3, 4, 1, 5, 1];
    
    let newArr = arr.filter(function(val){
        return val !== 1;
    });
    //newArr => [2, 3, 4, 5]
    

    Or by using the splice() method as:

    let arr = [1, 11, 2, 11, 3, 4, 5, 11, 6, 11];
        for (let i = 0; i < arr.length-1; i++) {
           if ( arr[i] === 11) {
             arr.splice(i, 1);
           }
        }
        console.log(arr);
        // [1, 2, 3, 4, 5, 6]
    

    Or suppose we want to delete del from the array arr:

    let arr = [1, 2, 3, 4, 5, 6];
    let del = 4;
    if (arr.indexOf(4) >= 0) {
        arr.splice(arr.indexOf(4), 1)
    }
    

    Or

    let del = 4;
    for(var i = arr.length - 1; i >= 0; i--) {
        if(arr[i] === del) {
           arr.splice(i, 1);
        }
    }
    
  4. If you know the element alone but not the position (or index) of the element, and want to delete just very first matching element using splice() method:

    let arr = [1, 11, 2, 11, 3, 4, 5, 11, 6, 11];
    
    for (let i = 0; i < arr.length-1; i++) {
      if ( arr[i] === 11) {
        arr.splice(i, 1);
        break;
      }
    }
    console.log(arr);
    // [1, 11, 2, 11, 3, 4, 5, 11, 6, 11]
    

The splice() method changes the contents of an array by removing or replacing existing elements and/or adding new elements.

array.splice(start[, deleteCount[, item1[, item2[, ...]]]])

start

The index at which to start changing the array (with origin 0). If greater than the length of the array, the actual starting index will be set to the length of the array. If negative, it will begin that many elements from the end of the array (with origin -1) and will be set to 0 if the absolute value is greater than the length of the array.

deleteCount Optional

An integer indicating the number of old array elements to remove.

If deleteCount is omitted, or if its value is larger than array.length - start (that is, if it is greater than the number of elements left in the array, starting at start), then all of the elements from start through the end of the array will be deleted. If deleteCount is 0 or negative, no elements are removed. In this case, you should specify at least one new element (see below).

item1, item2, ... Optional

The elements to add to the array, beginning at the start index. If you don't specify any elements, splice() will only remove elements from the array.

For more references, kindly go through:

Array.prototype.splice()

Take profit of reduce method as follows:

Case a) if you need to remove an element by index:

function remove(arr, index) {
  return arr.reduce((prev, x, i) => prev.concat(i !== index ? [x] : []), []);
}

case b) if you need to remove an element by the value of the element (int):

function remove(arr, value) {
  return arr.reduce((prev, x, i) => prev.concat(x !== value ? [x] : []), []);
}

So in this way we can return a new array (will be in a cool functional way - much better than using push or splice) with the element removed.

Splice, filter and delete to remove an element from an array

Every array has its index, and it helps to delete a particular element with their index.

The splice() method

array.splice(index, 1);    

The first parameter is index and the second is the number of elements you want to delete from that index.

So for a single element, we use 1.

The delete method

delete array[index]

The filter() method

If you want to delete an element which is repeated in an array then filter the array:

removeAll = array.filter(e => e != elem);

Where elem is the element you want to remove from the array and array is your array name.

Oftentimes it's better to just create a new array with the filter function.

let array = [1,2,3,4];
array = array.filter(i => i !== 4); // [1,2,3]

This also improves readability IMHO. I'm not a fan of slice, although it know sometimes you should go for it.

[2,3,5].filter(i => ![5].includes(i))

You can extend the array object to define a custom delete function as follows:

let numbers = [1,2,4,4,5,3,45,9];

numbers.delete = function(value){
    var indexOfTarget = this.indexOf(value)

    if(indexOfTarget !== -1)
    {
        console.log("array before delete " + this)
        this.splice(indexOfTarget, 1)
        console.log("array after delete " + this)
    }
    else{
        console.error("element " + value + " not found")
    }
}
numbers.delete(888)
// Expected output:
// element 888 not found
numbers.delete(1)

// Expected output;
// array before delete 1,2,4,4,5,3,45,9
// array after delete 2,4,4,5,3,45,9

Non in-place solution

arr.slice(0,i).concat(arr.slice(i+1));

let arr = [10, 20, 30, 40, 50]

let i = 2 ; // position to remove (starting from 0)
let r = arr.slice(0,i).concat(arr.slice(i+1));

console.log(r);

Remove single element

function removeSingle(array, element) {
    const index = array.indexOf(element)
    if (index >= 0) {
        array.splice(index, 1)
    }
}

Remove multiple elements, in-place

This is more complicated to ensure the algorithm runs in O(N) time.

function removeAll(array, element) {
    let newLength = 0
    for (const elem of array) {
        if (elem !== number) {
            array[newLength++] = elem
        }
    }
    array.length = newLength
}

Remove multiple elements, creating new object

array.filter(elem => elem !== number)

You can create an index with an all accessors example:

<div >
</div>

function getIndex($id){
  return (
    this.removeIndex($id)
    alert("This element was removed")
  )
}


function removeIndex(){
   const index = $id;
   this.accesor.id.splice(index.id) // You can use splice for slice index on
                                    // accessor id and return with message
}
<div>
    <fromList>
        <ul>
            {...this.array.map( accesors => {
                <li type="hidden"></li>
                <li>{...accesors}</li>
            })

            }
        </ul>
    </fromList>

    <form id="form" method="post">
        <input  id="{this.accesors.id}">
        <input type="submit" callbackforApplySend...getIndex({this.accesors.id}) name="sendendform" value="removeIndex" >
    </form>
</div>

I would like to suggest to remove one array item using delete and filter:

var arr = [1,2,3,4,5,5,6,7,8,9];
delete arr[5];
arr = arr.filter(function(item){ return item != undefined; });
//result: [1,2,3,4,5,6,7,8,9]

So, we can remove only one specific array item instead of all items with the same value.

Most of the answers here give a solution using -

  1. indexOf and splice
  2. delete
  3. filter
  4. regular for loop

Although all the solutions should work with these methods, I thought we could use string manipulation.

Points to note about this solution -

  1. It will leave holes in the data (they could be removed with an extra filter)
  2. This solution works for not just primitive search values, but also objects.

The trick is to -

  1. stringify input data set and the search value
  2. replace the search value in the input data set with an empty string
  3. return split data on delimiter ,.
    remove = (input, value) => {
        const stringVal = JSON.stringify(value);
        const result = JSON.stringify(input)

        return result.replace(stringVal, "").split(",");
    }

A JSFiddle with tests for objects and numbers is created here - https://jsfiddle.net/4t7zhkce/33/

Check the remove method in the fiddle.

Remove the particular array item

Enter image description here

var cars = ["Apple", "Banana", "Mango", "Orange", "Grapes"];

document.getElementById("demo").innerHTML = cars;

for( var i = 0; i < cars.length; i++){
   if ( cars[i] === "Banana") {
     cars.splice(i, 1);
     i--;
   }
}

document.getElementById("demo2").innerHTML =  cars;
p {
  font-size: 20px;
  padding: 10px;
  border: 1px dashed tan;
  color: brown;
}
<!DOCTYPE html>
<html>
<body>

<h2>Before</h2>
<p id="demo"></p>
<h2>After</h2>
<p id="demo2"></p>
</body>
</html>

You can create a prototype for that. Just pass the array element and the value which you want to remove from the array element:

Array.prototype.removeItem = function(array,val) {
    array.forEach((arrayItem,index) => {
        if (arrayItem == val) {
            array.splice(index, 1);
        }
    });
    return array;
}
var DummyArray = [1, 2, 3, 4, 5, 6];
console.log(DummyArray.removeItem(DummyArray, 3));

To find and remove a particular string from an array of strings:

var colors = ["red","blue","car","green"];
var carIndex = colors.indexOf("car"); // Get "car" index
// Remove car from the colors array
colors.splice(carIndex, 1); // colors = ["red", "blue", "green"]

Source: https://www.codegrepper.com/?search_term=remove+a+particular+element+from+array

Performance

Today (2019-12-09) I conduct performance tests on macOS v10.13.6 (High Sierra) for chosen solutions. I show delete (A), but I not use it in comparison with other methods, because it left empty space in the array.

The conclusions

  • the fastest solution is array.splice (C) (except Safari for small arrays where it has the second time)
  • for big arrays, array.slice+splice (H) is the fastest immutable solution for Firefox and Safari; Array.from (B) is fastest in Chrome
  • mutable solutions are usually 1.5x-6x faster than immutable
  • for small tables on Safari, surprisingly the mutable solution (C) is slower than the immutable solution (G)

Details

In tests I remove middle element from the array in different ways. The A, C solutions are in-place. The B, D, E, F, G, H solutions are immutable.

Results for array with 10 elements

Enter image description here

In Chrome the array.splice (C) is the fastest in-place solution. The array.filter (D) is the fastest immutable solution. The slowest is array.slice (F). You can perform the test on your machine here.

Results for array with 1.000.000 elements

Enter image description here

In Chrome the array.splice (C) is the fastest in-place solution (the delete (C) is similar fast - but it left an empty slot in the array (so it does not perform a 'full remove')). The array.slice-splice (H) is the fastest immutable solution. The slowest is array.filter (D and E). You can perform the test on your machine here.

var a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
var log = (letter,array) => console.log(letter, array.join `,`);

function A(array) {
  var index = array.indexOf(5);
  delete array[index];
  log('A', array);
}

function B(array) {
  var index = array.indexOf(5);
  var arr = Array.from(array);
  arr.splice(index, 1)
  log('B', arr);
}

function C(array) {
  var index = array.indexOf(5);
  array.splice(index, 1);
  log('C', array);
}

function D(array) {
  var arr = array.filter(item => item !== 5)
  log('D', arr);
}

function E(array) {
  var index = array.indexOf(5);
  var arr = array.filter((item, i) => i !== index)
  log('E', arr);
}

function F(array) {
  var index = array.indexOf(5);
  var arr = array.slice(0, index).concat(array.slice(index + 1))
  log('F', arr);
}

function G(array) {
  var index = array.indexOf(5);
  var arr = [...array.slice(0, index), ...array.slice(index + 1)]
  log('G', arr);
}

function H(array) {
  var index = array.indexOf(5);
  var arr = array.slice(0);
  arr.splice(index, 1);
  log('H', arr);
}

A([...a]);
B([...a]);
C([...a]);
D([...a]);
E([...a]);
F([...a]);
G([...a]);
H([...a]);
This snippet only presents code used in performance tests - it does not perform tests itself.

Comparison for browsers: Chrome v78.0.0, Safari v13.0.4, and Firefox v71.0.0

Enter image description here

Remove a specific element from an array can be done in one line with the filter option, and it's supported by all browsers: https://caniuse.com/#search=filter%20array

function removeValueFromArray(array, value) {
    return array.filter(e => e != value)
}

I tested this function here: https://bit.dev/joshk/jotils/remove-value-from-array/~code#test.ts

You can use splice to remove objects or values from an array.

Let's consider an array of length 5, with values 10,20,30,40,50, and I want to remove the value 30 from it.

var array = [10,20,30,40,50];
if (array.indexOf(30) > -1) {
   array.splice(array.indexOf(30), 1);
}
console.log(array); // [10,20,40,50]

I found this blog post which is showing nine ways to do it:

9 Ways to Remove Elements From A JavaScript Array - Plus How to Safely Clear JavaScript Arrays

I prefer to use filter():

var filtered_arr = arr.filter(function(ele){
   return ele != value;
})

You can use

Array.splice(index);

If the array contains duplicate values and you want to remove all the occurrences of your target then this is the way to go...

let data = [2, 5, 9, 2, 8, 5, 9, 5];
let target = 5;
data = data.filter(da => da !== target);

Note: - the filter doesn't change the original array; instead it creates a new array.

So assigning again is important.

That's led to another problem. You can't make the variable const. It should be let or var.

Following are some methods that might help you in removing specific item from Array.

1. Array filter Method to Remove Items By Value

Unlike the splice method, filter creates a new array. filter() does not mutate the array on which it is called, but returns a new array.

filter() has a single parameter, a callback method. The callback is triggered as the filter method iterates through the array elements. It will pass three values to the callback: the current value or element, the current array index and the full array.

The callback method should return either true or false. It is your responsibility to test the value (element) to see if it meets your criteria. If it does you can return true. Elements that return true are added to the new, filtered array.

var array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0];

var filtered = array.filter(function(value, index, arr){

    return value > 5;

});

//filtered => [6, 7, 8, 9]
//array => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]

You should note a new array containing matching values is returned. The original array is left untouched. I find this useful because I often want to retain an original data source, but retrieve subsets based on different logic sets.

2. The Lodash Array Remove Method

Sometimes utility libraries are the best way to solve more complex problems. Lodash provides a rich set of array manipulation methods, one being remove.

The Lodash remove method works much like the array filter method, but sort of in reverse. It does not save the original array values, but removes matching elements. It returns the matching elements as a new array.

var array = [1, 2, 3, 4];
var evens = _.remove(array, function(n) {
  return n % 2 === 0;
});

console.log(array);
// => [1, 3]

console.log(evens);
// => [2, 4]

3. Making a Remove Method

As I mentioned before, there is no native Array.remove method. The Lodash method does solve this problem, but you may not always want to use Lodash. This does not mean you cannot create a utility method. John Resig gave us a model to follow, however he extended the Array prototype, which is a bad idea.

Instead I created an Array remove utility method that can be added to a helper or utility library. Like the Lodash remove method the first parameter is the target array. It uses Array.filter to return elements not matching a value.

function arrayRemove(arr, value) {

   return arr.filter(function(ele){
       return ele != value;
   });

}

var result = arrayRemove(array, 6);

// result = [1, 2, 3, 4, 5, 7, 8, 9, 0]

This method is simple, and it assumes simple values like numbers or strings. You could modify this method to use a custom comparison method, but I think it would be easier to just use the filter method directly.

4. Explicitly Remove Array Elements Using the Delete Operator

You can remove specific array elements using the delete operator:

var ar = [1, 2, 3, 4, 5, 6];
delete ar[4]; // Delete element with index 4
console.log( ar ); // [1, 2, 3, 4, undefined, 6]
alert( ar ); // 1, 2, 3, 4, , 6

Using the delete operator does not affect the length property. Nor does it affect the indexes of subsequent elements. The array becomes sparse, which is a fancy way of saying the deleted item is not removed but becomes undefined. Compare using delete with the splice method described below.

The delete operator is designed to remove properties from JavaScript objects, which arrays are objects.

The reason the element is not actually removed from the array is the delete operator is more about freeing memory than deleting an element. The memory is freed when there are no more references to the value.

ES10 Update

This post summarizes common approaches to element removal from array as of ECMAScript 2019 (ES10).

1. General cases

1.1. Removing Array element by value using .splice()

| In-place: Yes |
| Removes duplicates: Yes(loop), No(indexOf) |
| By value / index: By index |

If you know the value you want to remove from an array you can use the splice method. First you must identify the index of the target item. You then use the index as the start element and remove just one element.

// With a 'for' loop
const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0];
for( let i = 0; i < arr.length; i++){
  if ( arr[i] === 5) {
    arr.splice(i, 1);
  }
} // => [1, 2, 3, 4, 6, 7, 8, 9, 0]

// With the .indexOf() method
const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0];
const i = arr.indexOf(5);
arr.splice(i, 1); // => [1, 2, 3, 4, 6, 7, 8, 9, 0]

1.2. Removing Array element using the .filter() method

| In-place: No |
| Removes duplicates: Yes |
| By value / index: By value |

Specific element can be filtered out from array, by providing filtering function. Such function is then called for every element in array.

const value = 3
let arr = [1, 2, 3, 4, 5, 3]
arr = arr.filter(item => item !== value)
console.log(arr)
// [ 1, 2, 4, 5 ]

1.3. Removing Array element by extending Array.prototype

| In-place: Yes/No (Depends on implementation) |
| Removes duplicates: Yes/No (Depends on implementation) |
| By value / index: By index / By value (Depends on implementation) |

Prototype of Array can be extended with additional methods. Such methods will be then available to use on created arrays.

Note: Extending prototypes of objects from standard library of JavaScript (like Array) is considered by some as an antipattern.

// In-place, removes all, by value implementation
Array.prototype.remove = function(item) {
    for (let i = 0; i < this.length; i++) {
        if (this[i] === item) {
            this.splice(i, 1);
        }
    }
}
const arr1 = [1,2,3,1];
arr1.remove(1) // arr1 equals [2,3]

// Non-stationary, removes first, by value implementation
Array.prototype.remove = function(item) {
    const arr = this.slice();
    for (let i = 0; i < this.length; i++) {
        if (arr[i] === item) {
            arr.splice(i, 1);
            return arr;
        }
    }
    return arr;
}
let arr2 = [1,2,3,1];
arr2 = arr2.remove(1) // arr2 equals [2,3,1]

1.4. Removing Array element using the delete operator

| In-place: Yes |
| Removes duplicates: No |
| By value / index: By index |

Using the delete operator does not affect the length property. Nor does it affect the indexes of subsequent elements. The array becomes sparse, which is a fancy way of saying the deleted item is not removed but becomes undefined.

const arr = [1, 2, 3, 4, 5, 6];
delete arr[4]; // Delete element with index 4
console.log( arr ); // [1, 2, 3, 4, undefined, 6]

The delete operator is designed to remove properties from JavaScript objects, which arrays are objects.

1.5. Removing Array element using Object utilities (>= ES10)

| In-place: No |
| Removes duplicates: Yes |
| By value / index: By value |

ES10 introduced Object.fromEntries, which can be used to create desired Array from any Array-like object and filter unwanted elements during the process.

const object = [1,2,3,4];
const valueToRemove = 3;
const arr = Object.values(Object.fromEntries(
  Object.entries(object)
  .filter(([ key, val ]) => val !== valueToRemove)
));
console.log(arr); // [1,2,4]

2. Special cases

2.1 Removing element if it's at the end of the Array

2.1.1. Changing Array length

| In-place: Yes |
| Removes duplicates: No |
| By value / index: N/A |

JavaScript Array elements can be removed from the end of an array by setting the length property to a value less than the current value. Any element whose index is greater than or equal to the new length will be removed.

const arr = [1, 2, 3, 4, 5, 6];
arr.length = 5; // Set length to remove element
console.log( arr ); // [1, 2, 3, 4, 5]
2.1.2. Using .pop() method

| In-place: Yes |
| Removes duplicates: No |
| By value / index: N/A |

The pop method removes the last element of the array, returns that element, and updates the length property. The pop method modifies the array on which it is invoked, This means unlike using delete the last element is removed completely and the array length reduced.

const arr = [1, 2, 3, 4, 5, 6];
arr.pop(); // returns 6
console.log( arr ); // [1, 2, 3, 4, 5]

2.2. Removing element if it's at the beginning of the Array

| In-place: Yes |
| Removes duplicates: No |
| By value / index: N/A |

The .shift() method works much like the pop method except it removes the first element of a JavaScript array instead of the last. When the element is removed the remaining elements are shifted down.

const arr = [1, 2, 3, 4];
arr.shift(); // returns 1
console.log( arr ); // [2, 3, 4]

2.3. Removing element if it's the only element in the Array

| In-place: Yes |
| Removes duplicates: N/A |
| By value / index: N/A |

The fastest technique is to set an array variable to an empty array.

let arr = [1];
arr = []; //empty array

Alternatively technique from 2.1.1 can be used by setting length to 0.

Deleting an element from array using ES6 spread operator.

Let's say you want to delete 4.

let array = [1,2,3,4,5]
const index = array.indexOf(4)
let new_array = [...array.slice(0,index), ...array.slice(index+1, array.length)]
console.log(new_array)
=> [1, 2, 3, 5]

Related