ajax跨域 node.js

const express = require('express');
const cors = require('cors');
const app = express();

// 允许所有源访问
app.use(cors());

// 或者配置特定的源
app.use(cors({
  origin: 'http://example.com',
  methods: ['GET', 'POST'],
  allowedHeaders: ['Content-Type', 'Authorization']
}));

app.get('/data', (req, res) => {
  res.json({ message: 'This is data from the server.' });
});

app.listen(3000, () => {
  console.log('Server is running on port 3000');
});

app.get('/data', (req, res) => {
  res.setHeader('Access-Control-Allow-Origin', '*');
  res.setHeader('Access-Control-Allow-Methods', 'GET, POST');
  res.setHeader('Access-Control-Allow-Headers', 'Content-Type');
  res.json({ message: 'This is data from the server.' });
});

fetch('http://yourserver.com/data')
  .then(response => response.json())
  .then(data => console.log(data))
  .catch(error => console.error('Error:', error));