Sometimes, we want to allow the Access-Control-Allow-Origin header using HTML5 fetch API with JavaScript.
In this article, we’ll look at how to allow the Access-Control-Allow-Origin header using HTML5 fetch API with JavaScript.
How to allow the Access-Control-Allow-Origin header using HTML5 fetch API with JavaScript?
To allow the Access-Control-Allow-Origin header using HTML5 fetch API with JavaScript, we should enable CORS on server side.
For instance, we write
const allowCrossDomain = (req, res, next) => {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Headers", "*");
next();
};
app.use(allowCrossDomain);
to call the Express app.use method to add the allowCrossDomain middleware into our app.
In it, we call res.header with the response header keys and values to enable CORS.
