node进阶｜ 解决表单enctype="multipart/form-data" 时获取不到Input值的问题

var app = express();
var express = require("express");
var router = require("./controller"); //前端MVC的C 一个顶层变量

{
    "main" :"router.js"
}

app.post("/file_upload",router.uploadfile);

exports.uploadfile=function(req,res){
         // console.log(req.route);
    var form = new formidable.IncomingForm();
        form.encoding = ‘utf-8‘;  
        form.uploadDir = "./uploads"; //上传路径
          form.parse(req, function(err, fields, files) { // 表单上传到东西在fields 文件在files里面
              //更改文件名
          var timeStr = (Math.floor(Math.random()*9000+1000)).toString();
          var d = sd.format(new Date(),‘YYYYMMDDHHmmss‘+timeStr);
          var folder = fields.folder;
          var extname = path.extname(files.file.name); //文件类型
          var oldName = files.file.path;
          var newName = "./public/image/"+folder+"/"+d + extname;
          console.log(newName);
          console.log(folder);
          fs.rename(oldName,newName);
          //成功页
          res.send("<a href = ‘/‘>返回</a>");

        });

}

<form style="width:40%;" method="post" action="/file_upload" enctype="multipart/form-data">
   <input type="file" id="exampleInputFile"  name="file">
　　<input type="submit" class="btn btn-default">上传</input>
</form>

var express = require(‘express‘);
var path = require(‘path‘);
var index = require(‘./routes/index‘);
var fs = require(‘fs‘);
var multer = require(‘multer‘);

app.use(‘/‘, index);
var storage = multer.diskStorage({
     
       destination: function (req, file, cb) {
            cb(null, ‘./uploads‘)  //设定文件上传路径
       }, 
     //给上传文件重命名，获取添加后缀名
      filename: function (req, file, cb) {
          console.log(file.originalname) //上传文件的名字
          console.log(file.mimetype)    //上传文件的类型
          console.log(file.fieldname) // 上传文件的Input的name名
          console.log(file.encoding)    // 编码方式
         var fileFormat = (file.originalname).split("."); //采用分割字符串，来获取文件类型
        console.log(fileFormat)
        var extname = path.extname(file.originalname); //path下自带方法去获取文件类型
        console.log(extname);
          // cb(null, file.fieldname + ‘-‘ + Date.now() + "." + fileFormat[fileFormat.length - 1]); //更改名字
          cb(null, file.fieldname + ‘-‘ + Date.now() +  extname); //更改名字
      }
 });
var upload = multer ({storage:storage}) //定制化上传参数
app.post(‘/upload‘, upload.array(‘logo‘,2), function(req, res, next){
    console.log(req.body.txt)
    res.send({ret_code: ‘0‘});
});

    <form action="/upload" method="post" enctype="multipart/form-data">
        <h2>单图上传</h2>
        <input type="file" name="logo">
        <input type="file" name="logo">
        <input type="text" name="txt">
        <input type="submit" value="提交">
    </form>