客户端：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
.box {
800px;
}
.box img {
100%;
}
.fbar {
800px;
height: 20px;
border: 1px solid #ccc;
border-radius: 5px;
overflow: hidden;
}
.bar {
0%;
background-color: blue;
text-align: center;
line-height: 20px;
}
</style>
</head>
<body>
<form id="form">
<input type="file" name="" id="file">
<div class="box" id="box">
</div>
<div class="fbar" id="fbar">
<div class="bar" id="bar">0%</div>
</div>
</form>
<script>
var form = document.getElementById('form')
var file = document.getElementById('file')
var bar = document.getElementById('bar')
var box = document.getElementById("box")
file.onchange = function() {
var formData = new FormData();
formData.append('attrName', this.files[0])
var xhr = new XMLHttpRequest();
xhr.open('post', 'http://localhost:3001/upload');
xhr.upload.onprogress = function(ev) {
var result = ev.loaded / ev.total * 100;
result = result.toFixed(2) + '%'
bar.innerHTML = result
bar.style.width = result
}
xhr.send(formData);
xhr.onload = function() {
var response = JSON.parse(xhr.responseText)
var img = document.createElement('img')
img.src = response.path
img.onload = function() {
box.appendChild(img)
}
}
}
</script>
</body>
</html>
服务端
app.post('/upload', (req, res) => {
const form = new formidable.IncomingForm()
form.uploadDir = path.join(__dirname, 'public', 'uploads')
form.keepExtensions = true
form.parse(req, (err, fields, files) => {
res.send({ path: files.attrName.path.split('public')[1] })
})
})