JSON.stringfy chinese garbled in node?

  node.js, question

After submitting the form, the browser will look at the Chinese character string and try to find a solution.

The index.htm file code is as follows:

 <form action="" method="GET">
 First Name: <input type="text" name="first_name">  <br>
 Last Name: <input type="text" name="last_name">
 <input type="submit" value="Submit">

Js file code is as follows:

var express = require('express');
 var app = express();
 app.get('/index.htm', function (req, res) {
 Res.sendFile( __dirname plus "/"plus "index.htm");
 app.get('/process_get', function (req, res) {
 //output JSON format
 response = {
 var server = app.listen(8081, function () {
 var host = server.address().address
 var port = server.address().port
 Log ("application instance, access address is http:// percent s: percent s", host, port)

Is the encoding of the browser utf-8?