js留言板网页设计代码大全

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>留言板</title>
    <style>
        /* 简单样式 */
        body {
            font-family: Arial, sans-serif;
        }
        #messages {
            width: 300px;
            height: 200px;
            border: 1px solid #ccc;
            overflow-y: scroll;
            padding: 10px;
        }
        #messageForm {
            margin-top: 10px;
        }
    </style>
</head>
<body>
    <h1>留言板</h1>
    <div id="messages"></div>
    <form id="messageForm">
        <input type="text" id="username" placeholder="用户名" required>
        <textarea id="userMessage" placeholder="你的留言" required></textarea>
        <button type="submit">提交</button>
    </form>

    <script src="script.js"></script>
</body>
</html>

document.getElementById('messageForm').addEventListener('submit', function(event) {
    event.preventDefault(); // 阻止表单默认提交行为

    const username = document.getElementById('username').value;
    const userMessage = document.getElementById('userMessage').value;

    if (username && userMessage) {
        const messageElement = document.createElement('div');
        messageElement.textContent = `${username}: ${userMessage}`;
        document.getElementById('messages').appendChild(messageElement);

        // 清空输入框
        document.getElementById('username').value = '';
        document.getElementById('userMessage').value = '';
    } else {
        alert('用户名和留言不能为空');
    }
});