Question

我的多部分（表单数据）上的POST请求有问题。其他主题中的所有想法都不起作用。

我使用快递， multer 和 postman
我完全删除了body-parser
上传文件但使用密钥无法访问数据。
当我尝试console.log(req.body);时，我获得undefined

这是我的代码：

app.js

＆＃13;

var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cors=require('cors');

//var index = require('./routes/index');
//var users = require('./routes/users');
var UsersDB=require('./routes/UsersDB');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(cors());
app.use(logger('dev'));
app.use(express.static(path.join(__dirname, 'public')));

//app.use('/', index);
//app.use('/users', users);
app.use('/Users',UsersDB);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});


module.exports = app;

＆＃13;

UsersDB.js

＆＃13;

var express = require('express');
var router = express.Router();
var Users=require('../models/Users');
var multer = require('multer');

var storage = multer.diskStorage({
  destination: function (req, file, cb) {
    cb(null, './uploads')
  },
  filename: function (req, file, cb) {
    cb(null, file.fieldname + '-' + Date.now() + ".png")
  }
});

var upload = multer({ storage: storage }).single('avatar');


//** POST **  ROUTE : http://localhost:3000/Users/       
router.post('/',function(req,res,next)
{
    console.log(req.body.firstName);

/*
    Users.addUsers(req.body,function(err,count)
    {
        if(err)
        {
            res.json(err);
        }
        else
        {
            res.json(req.body);//or return count for 1 &amp;amp;amp; 0
        }
    });
*/
    upload(req, res, function (err) {
    if (err) {
      // An error occurred when uploading
      return
    }
    // Everything went fine
  })

});

module.exports=router;

＆＃13;

邮差错误：

＆＃13;

<!DOCTYPE html>
<html>
    <head>
        <title></title>
        <link rel="stylesheet" href="/stylesheets/style.css">
    </head>
    <body>
        <h1>Cannot read property 'firstName' of undefined</h1>
        <h2></h2>
        <pre>TypeError: Cannot read property 'firstName' of undefined
    at /mnt/c/Users/Elodie/Desktop/server/routes/UsersDB.js:69:25
    at Layer.handle [as handle_request] (/mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/layer.js:95:5)
    at next (/mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/route.js:137:13)
    at Route.dispatch (/mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/route.js:112:3)
    at Layer.handle [as handle_request] (/mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/layer.js:95:5)
    at /mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/index.js:281:22
    at Function.process_params (/mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/index.js:335:12)
    at next (/mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/index.js:275:10)
    at Function.handle (/mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/index.js:174:3)
    at router (/mnt/c/Users/Elodie/Desktop/server/node_modules/express/lib/router/index.js:47:12)</pre>
    </body>
</html>

＆＃13;

Answer 1

由于您正在使用multer来解析请求正文，因此您需要在访问req.body之前调用multer。您当前使用multer的方式，它将从请求中提取信息以处理文件，但不会成为中间件堆栈的一部分，因此在调用路由之前，您无法获得正文解析的好处。

将multer中间件添加到路由签名中，因此在调用路由回调之前，multer将解析请求主体。例如像这样

router.post('/', upload.single('avatar'), (req, res, next) => {
  console.log(req.body.firstName)
})

req.body undefined multipart

1 个答案: