JavaScript¶
JavaScript 模块¶
模块化，指的是将复杂项目下 JavaScript 程序拆分为可按需导入的单独模块的机制。
custom.js
export const name = "Custom"; // named export
export const greet = () => {
// named export
return "Hello World";
};
export class Person {
// named export
constructor() {
// ...
}
}
const add = (a, b) => a + b;
export default add; // default export, only one per module
main.js
// import as needed, renaming is optional
import { name, greet as greeting } from "./custom.js";
import add from "./custom.js";
// import { default as add } from "./custom.js"
console.log(name);
console.log(greeting());
console.log(add(1, 2));
// dynamic import
import("./custom.js").then((module) => {
// do something with module
});
在 HTML 中，使用 <script type="module"> 标签来加载模块。