【进阶篇】JavaScript代码规范

易读、易复用、易重构的 JavaScript 代码规范

1.变量命名规范有意义

Bad:

const yyyymmdstr = moment().format("YYYY/MM/DD");
Good:

const currentDate = moment().format("YYYY/MM/DD");

Bad: const yyyymmdstr = moment().format("YYYY/MM/DD"); Good: const currentDate = moment().format("YYYY/MM/DD");

2. 给变量定义名字

Bad:

// What the heck is 86400000 for?
setTimeout(blastOff, 86400000);
Good:

// Declare them as capitalized named constants.
const MILLISECONDS_IN_A_DAY = 86_400_000;

setTimeout(blastOff, MILLISECONDS_IN_A_DAY);

Bad: // What the heck is 86400000 for? setTimeout(blastOff, 86400000); Good: // Declare them as capitalized named constants. const MILLISECONDS_IN_A_DAY = 86_400_000; setTimeout(blastOff, MILLISECONDS_IN_A_DAY);

3.函数的变量定义初始值

Bad:

function createMicrobrewery(name) {
  const breweryName = name || "Hipster Brew Co.";
  // ...
}
Good:

function createMicrobrewery(name = "Hipster Brew Co.") {
  // ...
}

Bad: function createMicrobrewery(name) { const breweryName = name || "Hipster Brew Co."; // ... } Good: function createMicrobrewery(name = "Hipster Brew Co.") { // ... }

4.函数的形参过多时候，用对象代替多个参数

Bad:

function createMenu(title, body, buttonText, cancellable) {
  // ...
}

Bad: function createMenu(title, body, buttonText, cancellable) { // ... }

Bad: const yyyymmdstr = moment().format("YYYY/MM/DD"); Good: const currentDate = moment().format("YYYY/MM/DD"); 2. 给变量定义名字 Bad: // What the heck is 86400000 for? setTimeout(blastOff, 86400000); Good: // Declare them as capitalized named constants. const MILLISECONDS_IN_A_DAY = 86_400_000; setTimeout(blastOff, MILLISECONDS_IN_A_DAY); 3.函数的变量定义初始值 Bad: function createMicrobrewery(name) { const breweryName = name || "Hipster Brew Co."; // ... } Good: function createMicrobrewery(name = "Hipster Brew Co.") { // ... } 4.函数的形参过多时候，用对象代替多个参数 Bad: function createMenu(title, body, buttonText, cancellable) { // ... }

易读、易复用、易重构的 JavaScript 代码规范 1.变量命名规范有意义 Bad: const yyyymmdstr = moment().format("YYYY/MM/DD"); Good: const currentDate = moment().format("YYYY/MM/DD"); 2. 给变量定义名字 Bad: // What the heck is 86400000 for? setTimeout(blastOff, 86400000); Good: // Declare them as capitalized named constants. const MILLISECONDS_IN_A_DAY = 86_400_000; setTimeout(blastOff, MILLISECONDS_IN_A_DAY); 3.函数的变量定义初始值 Bad: function createMicrobrewery(name) { const breweryName = name || "Hipster Brew Co."; // ... } Good: function createMicrobrewery(name = "Hipster Brew Co.") { // ... } 4.函数的形参过多时候，用对象代替多个参数 Bad: function createMenu(title, body, buttonText, cancellable) { // ... }