在不使用<form>的情况下将图像上传到Node.JS服务器

<input type="file" id="imageInput">

const fileInput = document.getElementById('imageInput');
const file = fileInput.files[0];

const reader = new FileReader();
reader.onload = function(event) {
  const base64Image = event.target.result;
  // 将base64Image发送到服务器
};
reader.readAsDataURL(file);

fetch('/upload', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({ image: base64Image })
})
.then(response => {
  // 处理服务器的响应
})
.catch(error => {
  // 处理错误
});

npm install multer

const express = require('express');
const multer = require('multer');

const app = express();
const upload = multer({ dest: 'uploads/' });

app.post('/upload', upload.single('image'), (req, res) => {
  // 处理上传的图像文件
});

const fs = require('fs');

app.post('/upload', upload.single('image'), (req, res) => {
  const image = req.file;
  const imagePath = image.path;
  const targetPath = `uploads/${image.originalname}`;

  fs.rename(imagePath, targetPath, (error) => {
    if (error) {
      // 处理错误
    } else {
      // 图像上传成功
    }
  });
});