how to send html file in express code example

Example 1: express sendfile html

var express = require('express');
var app = express();
var path = require('path');

// viewed at http://localhost:8080
app.get('/', function(req, res) {
    res.sendFile(path.join(__dirname + '/index.html'));
});

app.listen(8080);

Example 2: send html file express

res.sendFile(path.join(__dirname + '/index.html'));

Example 3: express send html file

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