how to use a html file in express code example

Example 1: express send html file

app.get('/test', function(req, res) {
    res.sendFile('test.html', {root: __dirname })
});

Example 2: render html in node js

render html in node js
-----------------------------
//server.js & index.html keep in same dir
app.use(express.static('./'));

app.get('/', function(req, res) { 
    res.render('index.html');
});