js 只能点赞一次

// 假设有一个点赞按钮
const likeButton = document.getElementById('like-button');
let hasLiked = false;

likeButton.addEventListener('click', async () => {
    if (hasLiked) {
        alert('你已经点过赞了！');
        return;
    }

    // 发送点赞请求到后端
    try {
        const response = await fetch('/api/like', {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify({ postId: '123' }) // 假设postId是你要点赞的帖子ID
        });

        if (response.ok) {
            hasLiked = true;
            likeButton.disabled = true; // 禁用按钮
            likeButton.innerText = '已点赞';
        } else {
            alert('点赞失败，请重试');
        }
    } catch (error) {
        console.error('Error:', error);
        alert('点赞失败，请重试');
    }
});

const express = require('express');
const app = express();
app.use(express.json());

const likes = {}; // 存储点赞状态

app.post('/api/like', (req, res) => {
    const { postId } = req.body;

    if (!postId) {
        return res.status(400).json({ message: '缺少postId' });
    }

    if (likes[postId]) {
        return res.status(400).json({ message: '你已经点过赞了' });
    }

    likes[postId] = true;
    res.status(200).json({ message: '点赞成功' });
});

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