I am creating an single page app in vanilla JavaScript. I want to organize my code in different files to make it modular, which means I should be able to access functions de
Here is a working example
file1.mjs
function log1() {
console.log('log1');
}
function log2() {
console.log('log2');
}
export { log1, log2 };
file2.mjs you must explicitly write .mjs
extension
import { log1, log2 } from './file1.mjs';
log1();
log2();
index.html Notice attribute type="module"
<body>
<script type="module" src="file2.mjs"></script>
</body>
Then you need a static server to get rid of CORS block.
$ yarn global add serve
$ serve ./
Finally go to http://localhost:5000
and it will work
Update: It is recommended to use .mjs file extension for modules instead of .js
Chrome (v70) has some kind of issues when working with import
syntax on the local files served using file
protocol. It is probably CORS blocking that can happen using file
protocol according to some articles. But Chrome also does not show CORS warning in the console in this case - which is strange. Therefore some kind of HTTP server is needed so the files are served via HTTP protocol (as Vu showed in his answer). Firefox v63 (probably >v60) doesn't have these issues and you can compose html
with js
modules using file://
protocol without a special server.
Also make sure to:
use file type extensions when importing (import { func1, func2 } from './file-B.js';
).
use type="module"
in html script
element (<script type="module" src="file-A.js"></script>
)