我TypeError: express.json()不是一个函数

Question

我是初学者，我一直在使用github-learning-lab。它声明使用app.use(bodyParse.json())来执行POST请求，但VSCode声明'body-parse'已弃用。

我在网上搜索了一下，大多数人说使用app.use(express.json())作为当前版本的Express

My express version: 4.17.1

我的节点版本:14.17.0

const express = require('express');
const app = express();
app.use(express.json());
app.use(express.urlencoded({ extended: false }))
const mockUserData = [
{name: 'Mark'},
{name: 'Jill'}
]
app.get('/users', function(req, res){
res.json({
success: true,
message: 'successfully got users. Nice!',
users: mockUserData
})
})
// colons are used as variables that can be viewed in the params
app.get('/users/:id', function(req,res){
console.log(req.params.id);
res.json({
success: true,
message: 'got one user',
user: req.params.id
})
})
app.post('/login', function(req,res){
// Typically passwords are encrypted using something like bcrypt before sending to database
const username = req.body.username;
const password = req.body.password;
// This should come from the database
const mockUsername = 'billyTheKid';
const mockPassword = 'superSecret';
if (username === mockUsername && password === mockPassword) {
// In practice, use JSON web token sign method here to make an encrypted token
res.json({
success: true,
message: 'password and username match!',
token: 'encrypted token goes here'
})
} else {
res.json({
success: false,
message: 'password and username do not match'
})
}
})
app.listen(8000, function(){
console.log('server is running')
})

Macs-MBP:node-express-course mac$ node server.js
/Users/mac/Documents/node-express-course/server.js:4
app.use(express.json());
^
TypeError: express.json is not a function
at Object.<anonymous> (/Users/mac/Documents/node-express-course/server.js:4:17)
at Module._compile (internal/modules/cjs/loader.js:1068:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1097:10)
at Module.load (internal/modules/cjs/loader.js:933:32)
at Function.Module._load (internal/modules/cjs/loader.js:774:14)
at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:72:12)

Macs-MBP:node-express-course mac$ head node_modules/express/package.json
{
"_from": "express",
"_id": "express@4.17.1",
"_inBundle": false,
"_integrity": "sha512-mHJ9O79RqluphRrcw2X/GTh3k9tVv8YcoyY4Kkh4WDMUYKRZUq0h1o0w2rrrxBqM7VoeUVqgb27xlEMXTnYt4g==",
"_location": "/express",
"_phantomChildren": {},
"_requested": {
"type": "tag",
"registry": true,

Answer 1

我重新安装了express。我可能在最初安装时犯了一个错误。我一开始就该试试的。谢谢你的帮助。

Answer 2

一个非常相似的事情发生在我身上，我试图运行中间件:

app.use(express.json())

但是有相同类型的error，然后我重新安装express，这个问题得到解决

Answer 3

首先你可以使用Bodyparser或者你应该重新安装它，但我建议使用Bodyparser