10个JavaScript常用编程技巧与语法特性解析

let a = 1;
let b = 2;
[a, b] = [b, a];
console.log(a); // 输出2
console.log(b); // 输出1

function getNumbers() {
  return [1, 2, 3];
}
const [a, b, c] = getNumbers();
console.log(a); // 输出1
console.log(b); // 输出2
console.log(c); // 输出3

function greet(name = 'Guest') {
  console.log(`Hello ${name}!`);
}
greet(); // 输出 Hello Guest!
greet('John'); // 输出 Hello John!

const arr1 = [1, 2, 3];
const arr2 = [4, 5, 6];
const mergedArr = [...arr1, ...arr2];
console.log(mergedArr); // 输出 [1, 2, 3, 4, 5, 6]

const name = 'John';
console.log(`Hello ${name}!`); // 输出 Hello John!

const numbers = [1, 2, 3];
const doubledNumbers = numbers.map(number => number * 2);
console.log(doubledNumbers); // 输出 [2, 4, 6]

const person = {
  name: 'John',
  age: 30,
  location: 'New York'
};
const { name, age } = person;
console.log(name); // 输出 John
console.log(age); // 输出 30

const person = {
  name: 'John',
  age: 30,
  location: 'New York'
};
const copiedPerson = { ...person };
console.log(copiedPerson); // 输出 {name: "John", age: 30, location: "New York"}

const message = `Hello,
World!`;
console.log(message); // 输出 Hello, \n World!

const promise1 = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve('Promise 1');
  }, 1000);
});
const promise2 = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve('Promise 2');
  }, 2000);
});
const promise3 = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve('Promise 3');
  }, 3000);
});
Promise.all([promise1, promise2, promise3])
  .then(values => console.log(values))
  .catch(error => console.log(error));