Section 1.1: Random Element Selection from an Array

Fetching a random item from an array is a breeze with the combination of Math.random() and the array's length:

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

const randomElement = arr[Math.floor(Math.random() * arr.length)];

console.log(randomElement);

Section 1.2: Flattening Nested Arrays

You can easily flatten arrays using the reduce() and concat() methods:

const arr = [[1, 2], [3, 4], [5, 6]];

const flattenedArr = arr.reduce((acc, cur) => acc.concat(cur), []);

console.log(flattenedArr); // Output: [1, 2, 3, 4, 5, 6]

Section 1.3: Sorting Arrays by a Specific Property

Sort an array of objects based on a specific property value with ease:

const sortedArray = array.sort((a, b) => (a.property > b.property ? 1 : -1));

Section 1.4: Filtering Out Unwanted Elements

You can swiftly remove specific elements from an array:

const removedArray = array.filter((item) => item !== elementToRemove);

Section 1.5: Checking for Duplicates in an Array

To determine if there are duplicates in an array:

const hasDuplicates = (array) => new Set(array).size !== array.length;

Section 1.6: Checking for the Existence of a Value

Quickly check if a value exists in an array:

const hasValue = arr.includes(value);

Section 1.7: Capitalizing the First Letter of a String

Transform the initial character of a string to uppercase:

const capitalized = str.charAt(0).toUpperCase() + str.slice(1);

Section 1.8: Generating a Random Integer

Create a random integer within a specified range:

const randomInt = Math.floor(Math.random() * (max - min + 1)) + min;

Section 1.9: Creating a Random String

Generate a random string of a defined length:

const randomStr = Math.random().toString(36).substring(2, length);

Section 1.10: Swapping Values of Variables

You can easily swap values between two variables using destructuring:

let a = 1, b = 2;

[b, a] = [a, b];

console.log(a, b); // 2, 1

Section 1.11: Converting a String to camelCase

Effortlessly convert any string to camelCase format:

const str = 'hello world';

const camelCase = str.replace(/s(.)/g, ($1) => $1.toUpperCase()).replace(/s/g, '').replace(/^(.)/, ($1) => $1.toLowerCase());

console.log(camelCase); // "helloWorld"

Section 1.12: Calculating Time Intervals

Determine the number of days between two dates:

const diffInDays = (dateA, dateB) => Math.floor((dateB - dateA) / (1000 * 60 * 60 * 24));

Section 1.13: Discovering the Day of the Year

Find out which day of the year a particular date falls on:

const dayOfYear = (date) => Math.floor((date - new Date(date.getFullYear(), 0, 0)) / 1000 / 60 / 60 / 24);

Section 1.14: Copying Text to Clipboard

Effortlessly copy text to your clipboard:

const copyToClipboard = (text) => navigator.clipboard.writeText(text);

copyToClipboard("Hello World");

Section 1.15: Identifying Variable Types

Determine the type of any variable in JavaScript:

const getType = (variable) => Object.prototype.toString.call(variable).slice(8, -1).toLowerCase();

getType(''); // string

Section 1.16: Checking if an Object is Empty

Quickly check whether an object contains no properties:

const isEmptyObject = (obj) => Object.keys(obj).length === 0 && obj.constructor === Object;

These concise JavaScript one-liners not only save time but also contribute to writing cleaner and more efficient code. Happy coding! 🎉