My client code:
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
<link rel="stylesheet" href="form.css" />
</head>
<body>
<form action="/login" method="post" class="form">
<input type="text" name="txt" class="txt" id="txt" placeholder="name" />
<input type="submit" class="submit" id="submit" />
</form>
<script defer src="https://cdn.jsdelivr.net/npm/axios/dist/axios.min.js"></script>
<script>
let submit = document.querySelector(".submit");
const form = document.querySelector(".form");
form.addEventListener("submit", (e) => {
e.preventDefault();
const formData = new FormData(form);
const formObject = {};
formData.forEach((value, key) => {
formObject[key] = value;
});
console.log(axios.defaults)
axios
.post("http://localhost:8080/login", formObject)
.then(function (response) {
console.log(response.data);
})
.catch(function (error) {
console.log(error);
});
});
</script>
</body>
</html>
My server side code:
const app = express();
const path = require("path");
app.use(express.static('./public',{index:'form.html'}));
app.use(express.urlencoded({extended:true}));
app.post('/login',(req,res)=>{
//const txt = req.body;
console.log('logged data: ',req.body);
res.send('Thanks');
})
app.listen(8080, () => {
console.log('server is running...in port 8080')
});
First of all please keep in mind that I am new to backend. When I try to console.log the logged data, it returns an empty object, I can't understand why my req.body returns an empty object, but when I try to do the same by giving action:"/login" and the method When: "post" inside the form tag it works as expected and gives me the input I provide. Please someone help me, my head is burning, thank you in advance.
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
req.bodyis empty because when you send it usingaxiosyou are actually sending a JSON (application/json) payload , and the backend doesn't have a JSON payload parser, only URL encoding, and the HTML form sends it inapplication/x-www-form-urlencodedformat, that's why it works.Therefore, you need to use axios to send URL-encoded requests, which you can do by using
URLSearchParamsto convert the JSON object into a query string. Try this.axios .post("http://localhost:8080/login", new URLSearchParams(formObject))Alternatively, just add a JSON parser to the backend and your raw JSON requests will work, using the built-in parser: