Array Methods

JavaScript provides several built-in methods to manipulate arrays efficiently:

1. push():

Adds one or more elements to the end of an array.

Example:

JavaScript
let fruits = ["Apple", "Banana"];
fruits.push("Mango");
console.log(fruits);  // Output: ["Apple", "Banana", "Mango"]

2. pop():

Removes the last element from an array and returns it.

Example:

JavaScript
let fruits = ["Apple", "Banana", "Mango"];
fruits.pop();
console.log(fruits);  // Output: ["Apple", "Banana"]

3. shift():

Removes the first element from an array and returns it.

Example:

JavaScript
let fruits = ["Apple", "Banana", "Mango"];
fruits.shift();
console.log(fruits);  // Output: ["Banana", "Mango"]

4. unshift()

Adds one or more elements to the beginning of an array.

Example:

JavaScript
let fruits = ["Banana", "Mango"];
fruits.unshift("Apple");
console.log(fruits);  // Output: ["Apple", "Banana", "Mango"]

5. slice()

Returns a shallow copy of a portion of an array into a new array, without modifying the original array.

Example:

JavaScript
let fruits = ["Apple", "Banana", "Mango", "Orange"];
let slicedFruits = fruits.slice(1, 3);
console.log(slicedFruits);  // Output: ["Banana", "Mango"]

6. splice()

Adds or removes elements at a specific index in the array. Unlike slice(), it modifies the original array.

Example:

JavaScript
let fruits = ["Apple", "Banana", "Mango"];
fruits.splice(1, 1, "Orange");
console.log(fruits);  // Output: ["Apple", "Orange", "Mango"]

7. map()

Creates a new array populated with the results of calling a provided function on every element in the array.

Example:

JavaScript
let numbers = [1, 2, 3, 4];
let doubled = numbers.map(num => num * 2);
console.log(doubled);  // Output: [2, 4, 6, 8]

8. filter()

Creates a new array with all elements that pass the test implemented by the provided function.

Example:

JavaScript
let numbers = [1, 2, 3, 4];
let even = numbers.filter(num => num % 2 === 0);
console.log(even);  // Output: [2, 4]

9. forEach()

Executes a provided function once for each array element.

Example:

JavaScript
let fruits = ["Apple", "Banana", "Mango"];
fruits.forEach(fruit => console.log(fruit));
// Output: 
// Apple
// Banana
// Mango

10. find()

Returns the first element in the array that satisfies the provided testing function.

Example:

JavaScript
let numbers = [5, 12, 8, 130, 44];
let found = numbers.find(num => num > 10);
console.log(found);  // Output: 12

11. some()

Checks if at least one element in the array passes the test implemented by the provided function.

Example:

JavaScript
let numbers = [1, 2, 3, 4];
let hasEven = numbers.some(num => num % 2 === 0);
console.log(hasEven);  // Output: true

12. every()

Checks if all elements in the array pass the test implemented by the provided function.

Example:

JavaScript
let numbers = [2, 4, 6, 8];
let allEven = numbers.every(num => num % 2 === 0);
console.log(allEven);  // Output: true
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