An article summarizing 5 JavaScript code optimization tips

In this article, we will introduce 5 code optimization tips to help write more efficient and elegant code. These techniques range from using spread operators to simplify code to using async/await to handle asynchronous code.

1. Use the spread operator to destructure objects and arrays

The spread operator is represented by three dots ... and can be used to destructure objects and arrays. For objects, it allows easy creation of a new object using a subset of the properties of another object.

const numbersObj = { a: 1, b: 2, c: 3 };
const newObject = { ...numbersObj, b: 4 };
console.log(newObject); // { a: 1, b: 4, c: 3 }

For arrays, the spread operator makes it easy to extract and manipulate array elements.

const numbersArray = [1, 2, 3, 4, 5];
const newArray = [...numbersArray.slice(0, 2), 6, ...numbersArray.slice(4)];
console.log(newArray); // [ 1, 2, 6, 5 ]

Regarding the destructuring operator, if you are interested, you can refer to:

• 5 common scenarios and examples of JavaScript destructuring assignment
• Let’s talk about object deconstruction in JavaScript

2. Use async/await to simplify asynchronous code

##async/await is a way to simplify JavaScript Methods for handling asynchronous code. It allows writing asynchronous code in a way that looks and behaves like synchronous code.

async function getData() {
    const response = await fetch("https://jsonplaceholder.typicode.com/posts");
    const data = await response.json();
    console.log(data);
}
getData();

The Proxy object is used to create a proxy for an object to implement interception and customization of basic operations (such as property lookup, assignment, enumeration, function calling, etc.).

const target = {};
const handler = {
    get: (target, prop) => {
        console.log(`获取属性：${prop}`);
        return target[prop];
    },
    set: (target, prop, value) => {
        console.log(`属性 ${prop} 更新为 ${value}`);
        target[prop] = value;
    },
};
const proxy = new Proxy(target, handler);

proxy.name = "DevPoint";
console.log(proxy.name);

Copy after login

if-else statements in JavaScript Abbreviation. This is a concise and efficient way of expressing conditions and their corresponding consequences.

const x = 5;
const result = x > 0 ? "positive" : "negative";
console.log(result); // positive

const age = 30;
const result =
    age < 18 ? "未成年人" : age >= 18 && age < 60 ? "成年人" : "老年人";
console.log(result); // 成年人

Immediately Invoked Function Expression (immediately invoked function expression). It is a function that is called when it is defined. A JavaScript function that is executed immediately and creates a private scope for the variable. This is useful for protecting data privacy as it ensures that variables declared in the IIFE cannot be accessed from outside.