Question

我正在制作一个小脚本来上传照片并将其保存到本地存储中。我正在为此使用Express和Muller。

我有一个带有上传字段的html页面（请参见下文）。我一按“上传照片”按钮，他就将照片发送到端点“ / upload”。在这里，只有当帖子“ req.file”为空时，他才应将照片以“ image.jpg”的名称保存在我的计算机上。

我只是想知道怎么回事？我想念什么吗？

App.js

const express = require("express");
const multer = require("multer");
const helpers = require("./helpers");

const app = express();
const port = process.env.PORT || 3000;
app.use(express.static(__dirname + "/"));

const storage = multer.diskStorage({
  destination: function (req, file, cb) {
    cb(null, "uploads/");
  },

  filename: function (req, file, cb) {
    cb(null, "image.jpg");
  },
});

app.listen(port, () => console.log(`Listening on port ${port}...`));

app.post("/upload", (req, res) => {
  let upload = multer({
    storage: storage,
    fileFilter: helpers.imageFilter,
  }).single("image");

  upload(req, res, function (err) {
    if (req.fileValidationError) {
      return res.send(req.fileValidationError);
    } else if (!req.file) {
      return res.send("Please select an image to upload");
    } else if (err instanceof multer.MulterError) {
      return res.send(err);
    } else if (err) {
      return res.send(err);
    }
    res.send(
      `You have uploaded this image: <hr/><img src="${req.file.path}" width="500"><hr /><a href="./">Upload another image</a>`
    );
  });
});

Helpers.js

const imageFilter = function(req, file, cb) {
    // Accept images only
    if (!file.originalname.match(/\.(jpg|JPG|jpeg|JPEG|png|PNG|gif|GIF)$/)) {
        req.fileValidationError = 'Only image files are allowed!';
        return cb(new Error('Only image files are allowed!'), false);
    }
    cb(null, true);
};
exports.imageFilter = imageFilter;

HTML页面

<form action="/upload" enctype="multipart/form-data" method="POST">
   <input type="file" name="image" accept="image/*" />
   <input type="submit" value="Upload Photo" />
</form>

Answer 1

在“常量存储”中出错了。我填写了错误的文件路径。但是奇怪的是req.file是空的...无论如何，它可以工作！

使用Muller上传图像后未找到图像

1 个答案: