当我通过 multer 上传图像时，我收到图像未定义错误

Question

我用node 和 mysql 用角度 5 使用它。

const express = require('express');
const mysql = require('mysql');
const bodyParser = require('body-parser');
const path = require('path');
const cors = require('cors');
const router = express.Router();
const multer = require('multer');
const storage = multer.diskStorage({
destination: function (req, file, cb) {
cb(null, './assets/images/')
},
filename: function (req, file, cb) {
cb(null, file.originalname)
}
});
const fileFilter = (req, file, cb)=>{
if(file.mimetype === 'image/jpeg' || file.mimetype === 'image/png'){
cb(null, true);
}
else{
cb(null, false);
}
};
upload = multer({
storage: storage,
limits:{
filesize : 1024 * 1024 * 5
},
fileFilter : fileFilter
});
const app = express();
//DATABASE CONNECTION
const connection = mysql.createConnection({
host: 'localhost',
user:'root',
password: 'root',
database: 'inpblog',
port: 8889
});
// ALLOW CROSS ORIGIN
const corsOptions = {
origin: 'http://localhost:4200',
origin1: 'http://localhost:4202',
optionsSuccessStatus: 200 // some legacy browsers (IE11, various SmartTVs) choke on 204
};
app.use(cors(corsOptions));
app.use('./assets/images', express.static(path.join(__dirname, 'dist', 'upload')));
const jsonParser = bodyParser.json();
const urlencodedParser = bodyParser.urlencoded({ extended: false });

connection.connect(function(error){
if(!!error){
console.log("error - db not connected");
}
else{
console.log("connected");
}
});

在这里，我定义了在mysql数据库中上传图像的代码。 通过邮递员，它使用 Multer 中间件在目标文件夹中上传图像，但是当我通过 ng 格式上传图像时，它在控制台中显示错误。image undefined"，并在MySQL中提交"C：/fakepath/image.jgg"。

这是插入帖子的API

app.post('/insertPost', upload.single('txt_blog_image'), jsonParser, (req, res) => {
console.log("image: ", req.file); // working fine only with postman
//console.log("rBody: ", req.body.txt_blog_image); // working fine only with Angular
let blogFields = {
post_author : req.body.txt_blog_author,
post_image : req.body.txt_blog_image
};
let sql = 'INSERT INTO insdb SET ?';
let query = connection.query(sql, blogFields, (err,result)=> {
res.send('New Post  added...');
});
});
// Get All Post
app.get('/getallposts', (req, res) => {
let sql = 'SELECT * FROM insdb';
let query = connection.query(sql, (err, results) => {
if(err) throw err;
console.log(results);
res.send(results);
});
});
app.get('*', (req, res) => {
res.sendFile(path.join(__dirname, 'dist/index.html'));
});
app.listen(4202);

Answer 1

试试这种方式。

var path = require('path');
var multer = require('multer');
var storage = multer.diskStorage({
destination: function(req, file, callback) {
callback(null, './assets/images/')
},
filename: function(req, file, callback) {
console.log(file)
callback(null, file.fieldname + '-' + Date.now() + path.extname(file.originalname))
}
})

在您的 api 中：

app.post('/getallposts',upload.single("image") , function(req, res) {
let sql = 'SELECT * FROM insdb';
let query = connection.query(sql, (err, results) => {
if(err) throw err;
console.log(results);
res.send(results);
});
})

从角度侧：

let form = new FormData();
form.append('image' , file); 

那么console在服务器端，req.files检查文件来了还是不来？

有关更多信息和示例，请参阅此链接