Nodejs如何把接收圖片base64格式保存為文件存儲到伺服器上

app.post('/upload', function(req, res){
//接收前臺POST過來的base64
var imgData = req.body.imgData;
//過濾data:URL
var base64Data = imgData.replace(/^data:image\/\w+;base64,/, "");
var dataBuffer = new Buffer(base64Data, 'base64');
fs.writeFile("image.png", dataBuffer, function(err) {
if(err){
res.send(err);
}else{
res.send("保存成功！");
}
});
});