Node.js TypeError:无法读取未定义的属性"文件"

Question

我只是在学习node.js,并且很难使用express和multer进行简单的文件上传.

这是表格:

上传图片

在我的configure.js身上:

app.use(express.static(path.join(__dirname, 'public')));
app.use(multer({dest:'../public/upload/temp'}).single('file'));

和image.js控制器:

create: function(req, res) {
        var saveImage = function() {
            console.log(req.body);
            var possible = 'abcdefghijklmnopqrstuvwxyz0123456789',
                imgUrl = '';

            for(var i=0; i < 6; i+=1) {
                imgUrl += possible.charAt(Math.floor(Math.random() * possible.length));
            }

            var tempPath = req.files.file.path, //<line 55 error
                ext = path.extname(req.files.file.name).toLowerCase(),
                targetPath = path.resolve('./public/upload/' + imgUrl + ext);

            if (ext === '.png' || ext === '.jpg' || ext === '.jpeg' || ext === '.gif') {


                fs.rename(tempPath, targetPath, function(err) {
                    if (err) throw err;

                    res.redirect('/images/' + imgUrl);
                });
            } else {
                fs.unlink(tempPath, function () {
                    if (err) throw err;

                    res.json(500, {error: 'Only image files are allowed.'});
                });
            }
        };

        saveImage();
    },

但是,当我尝试上传图片时出现此错误:

TypeError: Cannot read property 'file' of undefined
    at saveImage (/home/pc/node-dev/test-proj/controllers/image.js:55:37)
    at module.exports.create (/home/pc/node-dev/test-proj/controllers/image.js:76:9)
    at Layer.handle [as handle_request] (/home/pc/node-dev/test-proj/node_modules/express/lib/router/layer.js:95:5)
    at next (/home/pc/node-dev/test-proj/node_modules/express/lib/router/route.js:131:13)
    at Route.dispatch (/home/pc/node-dev/test-proj/node_modules/express/lib/router/route.js:112:3)
    at Layer.handle [as handle_request] (/home/pc/node-dev/test-proj/node_modules/express/lib/router/layer.js:95:5)
    at /home/pc/node-dev/test-proj/node_modules/express/lib/router/index.js:277:22
    at Function.process_params (/home/pc/node-dev/test-proj/node_modules/express/lib/router/index.js:330:12)
    at next (/home/pc/node-dev/test-proj/node_modules/express/lib/router/index.js:271:10)
    at urlencodedParser (/home/pc/node-dev/test-proj/node_modules/body-parser/lib/types/urlencoded.js:95:37)

当我记录req对象时,file不存在:

{ title: 'myimage', description: 'something' }

实际上这个片段只是我在本书中读到的一个稍微修改过的版本,它使用的是过时的express-3.所以基本上我只是用multer部分更新了它.

我想知道这里有什么问题以及如何解决它.

Answer 1

您正在使用upload.single,你应该使用它req.file不是req.files.要上传多个文件,请使用upload.array.

请注意,您不需要再.file后req.file.req.file是您上传的文件upload.single.