Remove Elements From a JavaScript Array
Here are the various methods to remove elements from a JavaScript Array
Remove elements from Array
1. Using pop() method
The pop() method removes and returns the last element of an array. This function decreases the length of the array by 1 every time the element is removed.
let a = ["Apple", "Banana", "Orange", "Mango"];
// Removing the last element
let pop = a.pop();
console.log("Removed Element: ", pop);
console.log("Updated Array: ", a);
Output
Removed Element: Mango Updated Array: [ 'Apple', 'Banana', 'Orange' ]
Please Read JavaScript Array Tutorial for complete understanding of JavaScript Array.
2. Using shift() Method
The shift() method is used to remove and return the first element of the array and reduce the size of the original array by 1.
let a = ["Apple", "Banana", "Orange", "Mango"];
// Removing the first element
let fEle = a.shift();
console.log("Removed Element: ", fEle);
console.log("Updated Array: ", a);
Output
Removed Element: Apple Updated Array: [ 'Banana', 'Orange', 'Mango' ]
3. Using splice() Method
The splice() method is used to modify the contents of an array by removing the existing elements and/or adding new elements.
let a = ["Apple", "Banana", "Orange", "Mango"];
// Removing the specified element
let rEle = a.splice(1, 1);
console.log("Removed Element: ", rEle);
console.log("Updated Array: ", a);
Output
Removed Element: [ 'Banana' ] Updated Array: [ 'Apple', 'Orange', 'Mango' ]
4. Using filter() Method
If we need to remove elements based on a condition, the filter() method is best option. It creates a new array with only the elements that meet the condition.
function isPositive(val) {
return val > 0;
}
let a = [10, 25, 30, -10, 32, -35];
let filtered = a.filter(isPositive);
console.log("Positive Array Elements: ", filtered);
Output
Positive Array Elements: [ 10, 25, 30, 32 ]
5. Using Delete Operator
The delete operator returns a boolean value true, if the element or property is removed from the array or object and false, if a function or variable is passed to remove.
let a = ["Apple", "Banana", "Orange", "Mango"];
// Delete Element at Index 2
let deleted = delete a[2];
console.log("Removed Element: ", deleted);
console.log("Updated Array: ", a);
Output
Removed Element: true Updated Array: [ 'Apple', 'Banana', <1 empty item>, 'Mango' ]
6. Using Array Reset
Removing the elements from an array using the manual clear and reset approach either by resetting the length of the array as 0 using the length property or by assigning the array to an empty array([]).
let a1 = ["Apple", "Banana", "Orange", "Mango"];
let a2 = [10, 20, 30, 40, 50];
// After Deleting Each Element of an Array
a1 = [];
a2.length = 0;
console.log("Updated Array1: ", a1);
console.log("Updated Array2: ", a2);
Output
Updated Array1: [] Updated Array2: []
7. Using for() Loop and New Array
A simple for loop will be run over the array and pushes all elements in the new array except the element that has to be removed.
let rEle = (a, n) => {
let newA = [];
for (let i = 0; i < a.length; i++) {
if (a[i] !== n) {
newA.push(a[i]);
}
}
return newA;
};
// Driver Code
let a = [10, 20, 30, 40, 50];
let rElement = 20;
let res = rEle(a, rElement);
console.log("Updated Array: ", res);
Output
Updated Array: [ 10, 30, 40, 50 ]
8. Using lodash _.remove() Method
We can remove the array elements using Lodash library. The lodash _.remove() method is used to remove the element from array. To use the lodash library, you need to install it locally on your system.
// Import Lodash Library
const _ = require('lodash');
// Declare and Initialize an Array
let a = [101, 98, 12, -1, 848];
// Using _.remove() Method to Remove Odd Number
let even= _.remove(a, function(n) {
return n % 2 == 0;
});
console.log("Remaining Odd Elements: ", a);
console.log("Removed Even Elements: ", even);
Output
Removed Odd Elements: 101, -1
Remaining Even Elements: 98, 12, 848
9. Using forEach() and splice() Methods
This method uses forEach to iterate over the array and indexOf to find the index of the element that needs to be removed. The splice method is then used to remove the element at that index.
// Function to remove specific element from a
function remEt(a, ele) {
a.forEach((item, index) => {
if (item === ele) {
a.splice(index, 1);
}
});
return a;
}
// Declare and Initialize an Array
let a = ["Apple", "Banana", "Orange", "Mango"];
// Remove Specific Item from Array
remEt(a, "Banana");
console.log("Updated Array: ", a);
Output
Updated Array: [ 'Apple', 'Orange', 'Mango' ]
