JavaScript Array Methods

JavaScript Array Methods provide powerful built-in functions to perform operations on array. These methods simplifies the operations like – adding, removing, searching, sorting, filtering, and other operations.

Here is an example that demonstrates the basic array operations.

// Initial array of numbers
let arr = [10, 20, 30, 40, 50];

// 1. Adding numbers to the array
arr.push(60); // Add 60 at the end
arr.unshift(5); // Add 5 at the beginning
console.log("After Adding Elements:", arr);
// Output: After Adding Elements: [ 5, 10, 20, 30, 40, 50, 60 ]


// 2. Filtering numbers greater than 50
let nums = arr.filter(num => num <= 30);
console.log("Numbers Less Than or Equal to 50:", nums);
// Output: Numbers Less Than or Equal to 50: [ 5, 10, 20, 30 ]


// 3. Doubling the values
let doubledNums = arr.map(num => num * 2);
console.log("Doubled Values:", doubledNums);
// Output: Doubled Values: [ 10,  20,  40, 60, 80, 100, 120 ]


// 4. Sorting in Descending Order
let sortedNums = arr.sort((a, b) => b - a);
console.log("Sorted in Descending Order:", sortedNums);
// Output: Sorted in Descending Order: [ 60, 50, 40, 30, 20, 10,  5 ]

Below are the list of all JavaScript array methods with their brief description.

Method/Property	Description
JavaScript Array() constructor	Creates a new array instance (Array object).
JavaScript Array.from() Method	Creates an array from an array-like or iterable object.
JavaScript Array.fromAsync() Method	Creates an array from an async iterable or promises.
JavaScript Array.isArray() Method	Checks if a value is an array.
JavaScript Array.of() Method	Creates an array from arguments provided.
JavaScript Array at() Method	Returns the element at a specific index, supporting negative indices.
JavaScript Array concat() Method	Merges two or more arrays into a new array.
JavaScript Array copyWithin() Method	Copies part of an array to another location within the same array.
JavaScript Array entries() Method	Returns an iterator with key-value pairs for array indices and values.
JavaScript Array every() Method	Tests if all elements pass a given condition.
JavaScript Array fill() Method	Fills elements with a static value from a start to an end index.
JavaScript Array filter() Method	Creates a new array with elements that pass a condition.
JavaScript Array find() Method	Returns the first element that satisfies a condition.
JavaScript Array findIndex() Method	Returns the index of the first element that satisfies a condition.
JavaScript Array findLast() Method	Returns the last element that satisfies a condition.
JavaScript Array findLastIndex() Method	Returns the index of the last element that satisfies a condition.
JavaScript Array flat() Method	Flattens nested arrays into a single-level array.
JavaScript Array flatMap() Method	Maps and flattens the array in one operation.
JavaScript Array forEach() Method	Executes a function for each array element.
JavaScript Array includes() Method	Checks if an array contains a specified value.
JavaScript Array indexOf() Method	Returns the index of the first occurrence of a value.
JavaScript Array join() Method	Joins all elements into a string using a specified separator.
JavaScript Array keys() Method	Returns an iterator for the array indices.
JavaScript Array lastIndexOf() Method	Returns the index of the last occurrence of a value.
JavaScript Array map() Method	Creates a new array by applying a function to each element.
JavaScript Array pop() Method	Removes and returns the last element of an array.
JavaScript Array push() Method	Adds one or more elements to the end of an array.
JavaScript Array reduce() Method	Reduces the array to a single value using a function.
JavaScript Array reduceRight() Method	Reduces the array to a single value, iterating from right to left.
JavaScript Array reverse() Method	Reverses the order of array elements.
JavaScript Array shift() Method	Removes and returns the first element of an array.
JavaScript Array slice() Method	Returns a shallow copy of part of an array.
JavaScript Array some() Method	Tests if at least one element passes a given condition.
JavaScript Array sort() Method	Sorts the array in place based on a comparison function.
JavaScript Array splice() Method	Adds or removes elements from an array at a specified index.
JavaScript Array toLocaleString() Method	Converts elements to strings using locale settings.
JavaScript Array toReversed() Method	Returns a new array with reversed elements without modifying the original array.
JavaScript Array toSorted() Method	Returns a new array with sorted elements without modifying the original array.
JavaScript Array toSpliced() Method	Returns a new array after splicing, without modifying the original array.
JavaScript Array toString() Method	Converts the array to a string of elements separated by commas.
JavaScript Array unshift() Method	Adds one or more elements to the beginning of an array.
JavaScript Array values() Method	Returns an iterator for the array values.
JavaScript Array with() Method	Returns a new array with an updated value at a specified index.
JavaScript Array length Property	Returns the number of elements in the array.