Question

app.post('/upload/image', multer({
  dest:  './public/users/',
  changeDest: function(dest, req, res) {
      var newDestination = dest ;
      var stat = null;
      try {
          stat = fs.statSync(newDestination);
      } catch (err) {
          fs.mkdirSync(newDestination);
      }
      if (stat && !stat.isDirectory()) {
          throw new Error("directory cant be created");
      }
      return newDestination
  }
  }), function(req, res) {
       res.send({"status":"success"})
  });

我尝试使用此代码，以便可以动态设置multer的路径以存储来自客户端的上载图片。但是这段代码给了我这个错误

    throw new Error(msg);
        ^

Error: Route.post() requires a callback function but got a [object Object]
    at Route.<computed> [as post] (/Volumes/MacExtnd/Programming/webshop/backend/node_modules/express/lib/router/route.js:202:15)
    at Function.app.<computed> [as post] (/Volumes/MacExtnd/Programming/webshop/backend/node_modules/express/lib/application.js:482:19)
    at Object.<anonymous> (/Volumes/MacExtnd/Programming/webshop/backend/server.js:733:5)

请任何人告诉我如何解决此错误？

Answer 1

multer(opts)返回具有.single()，.none()之类的属性的对象。 See docs here。

您正在将此对象作为Express中间件函数传递，该函数解释了该错误。您可能想要选择正确的属性，然后传递该属性。

文档示例：

var upload = multer({ dest: 'uploads/' })

var app = express()

app.post('/profile', upload.single('avatar'), function (req, res, next) {
  // req.file is the `avatar` file
  // req.body will hold the text fields, if there were any
})

尝试将Multer用于动态路径时，为什么会出现此错误？

1 个答案: