Express-handlebars 说引擎未定义，为什么？

Question

I installed express-handlebars and i tried this

const express = require("express");
const exphbs = require('express-handlebars');
const app = express();

app.engine('.hbs', engine({defaultLayout: 'main', extname: '.hbs'}));
app.set('view engine', '.hbs');

and I get ReferenceError: engine is not defined

Answer 1

I changed from

app.engine('.hbs', engine({defaultLayout: 'main', extname: '.hbs'}));

to

app.engine('.hbs', exphbs.engine({defaultLayout: 'main', extname: '.hbs'}));

and it worked