我正在为一个Udacity课程开发一个示例项目,并且为此感到惊讶。我试图从表单中捕获一些用户输入并发出发布请求以返回javascript对象,当我尝试使用节点js运行服务器时,出现错误:
TypeError: Cannot read property 'body' of undefined
这是项目的服务器代码:
server.js
projectData = {};
/* Express to run server and routes */
const express = require('express');
/* Start up an instance of app */
const app = express();
/* Dependencies */
const bodyParser = require('body-parser')
/* Middleware*/
app.use(express.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
const cors = require('cors');
app.use(cors());
/* Initialize the main project folder*/
app.use(express.static('project1'));
const port = 8000;
/* Spin up the server*/
const server = app.listen(port, listening);
function listening(){
// console.log(server);
console.log(`running on localhost: ${port}`);
};
// GET route
const animalData = [];
app.get('/all', getData);
function getData(req, res){
res.send(AnimalData)
console.log(AnimalData)
}
// function sendData (request, response) {
// response.send(projectData);
// };
// POST route
app.post('/add', callBack);
function callBack(req,res){
res.send('POST received');
}
// POST an animal
const data = [];
// TODO-Call Function
app.route('/addAnimal')
.get(function (req, res) {
res.sendFile('index.html', {root: 'project1'})
})
.post(addAnimal())
function addAnimal(req, res){
newEntry = {
animal: req.body.animal,
facts: req.body.fact,
fav: req.body.fav
}
data.push(req.body);
res.status(200).send(req.body);
animalData.push(newEntry)
res.send(animalData)
console.log(animalData)
};
这是客户端的代码:
app.js
function performActuion(e){
const fav = document.getElementById('fav').value;
const getAnimal = async (url) =>{
const res = await fetch(url);
try {
const data = await res.json();
console.log(data)
return data;
} catch(error) {
console.log()
}
};
/* Function to POST data */
const postData = async ( url = '', data = {})=>{
console.log(data);
const response = await fetch(url, {
method: 'POST', // *GET, POST, PUT, DELETE, etc.
credentials: 'same-origin', // include, *same-origin, omit
headers: {
'Content-Type': 'application/json',
},
body: JSON.stringify(data), // body data type must match "Content-Type" header
});
try {
const newData = await response.json();
console.log(newData);
// console.log(newData);
return newData.json()
console.log(await response.json());
return await response.json()
}catch(error) {
console.log("error", error);
// appropriately handle the error
};
};
// TODO-Call Function
(async function(){
let res = await postData('/addAnimal', (animal: data.animal, fact: data.fact, fav: fav));;
console.log(res);
})();
在本课程的示例中,该代码似乎可以正常工作,但是当我尝试在自己的终端上运行它时,我什至无法进行测试,因为遇到类型错误。任何帮助将不胜感激。
谢谢, 迈克
答案 0 :(得分:0)
问题出在此代码中:
app.route('/addAnimal')
.get(function (req, res) {
res.sendFile('index.html', {root: 'project1'})
})
.post(addAnimal())
您实际上是在调用函数而不是将其用作回调,请使用以下代码:
app.route('/addAnimal')
.get(function (req, res) {
res.sendFile('index.html', {root: 'project1'})
})
.post(addAnimal)