[Answer] What Are Some Short but Amazing JavaScript Snippets?

[Answer] What Are Some Short but Amazing JavaScript Snippets?

Some short but amazing JavaScript snippets:

• Reverse a string:

const reverseString = str => str.split("").reverse().join("");

• Check whether a string is a palindrome:

const isPalindrome = str => str === str.split("").reverse().join("");

• Find the maximum value in an array:

const arr = [1, 2, 3, 4, 5];
const maxNum = Math.max(...arr);

• Remove duplicates from an array:

const arr = [1, 1, 2, 2, 3, 4, 4, 5];
const uniqueArr = [...new Set(arr)];

• Calculate the sum of an array:

const arr = [1, 2, 3, 4, 5];
const sum = arr.reduce((total, num) => total + num);

• Swap the values of two variables:

let a = 1, b = 2;
[b, a] = [a, b];

• Filter array elements that match a condition:

const arr = [1, 2, 3, 4, 5];
const filteredArr = arr.filter(num => num % 2 === 0);

• Flatten an array:

const arr = [1, [2, [3, [4]]]];
const flattenedArr = arr.flat(Infinity);

• Shuffle an array:

const arr = [1, 2, 3, 4, 5];
const shuffledArr = arr.sort(() => Math.random() - 0.5);

• Debounce:

const debounce = (func, delay) => {
  let timer;
  return (...args) => {
    clearTimeout(timer);
    timer = setTimeout(() => func(...args), delay);
  };
};

• Throttle:

const throttle = (func, limit) => {
  let inThrottle;
  return (...args) => {
    if (!inThrottle) {
      inThrottle = true;
      func(...args);
      setTimeout(() => inThrottle = false, limit);
    }
  };
};

• Check whether a variable is an array:

const arr = [1, 2, 3];
const isArray = Array.isArray(arr);

• Destructure object properties:

const obj = { x: 1, y: 2 };
const { x, y } = obj;

• Deep copy an object:

const deepCopy = obj => JSON.parse(JSON.stringify(obj));

• Calculate the average of an array:

const arr = [1, 2, 3, 4, 5];
const average = arr.reduce((total, num) => total + num) / arr.length;

• Check whether a string starts with a specific substring:

const str = "Hello, world!";
const startsWithHello = str.startsWith("Hello");

• Check whether a string ends with a specific substring:

const str = "Hello, world!";
const endsWithWorld = str.endsWith("world!");

• Quickly check whether a number is even:

const isEven = num => (num & 1) === 0;

• Format a number as currency:

const amount = 12345.67;
const formattedAmount = amount.toLocaleString("en-US", { style: "currency", currency: "USD" });

• Create an array with a specified length and default value:

const length = 5;
const defaultValue = 0;
const arr = Array.from({ length }, () => defaultValue);

• Use Promise.all to handle multiple async operations in parallel:

const urls = ["https://example.com/api/1", "https://example.com/api/2", "https://example.com/api/3"];
const requests = urls.map(url => fetch(url));
const responses = await Promise.all(requests);
const data = await Promise.all(responses.map(response => response.json()));

These snippets are also efficient and easy to use, but in real projects you should still pay attention to context and usage scenarios to ensure correctness and effectiveness.