: 文档标题标签</h1>
<p class="page-updated">最后更新：2026-09-12</p>
<h2><title>文档标题标签</h2>
<p class="tutorial-intro">定义文档的标题，显示在浏览器标签页和搜索引擎结果中；每个 HTML 文档应且只能有一个 title，且必须放在 head 内。</p>
<div class="tag-quickinfo"><table class="ref-detail-table"><tbody>
<tr><th>分类</th><td><span class="tag-badge badge-cat">元数据</span></td></tr>
<tr><th>内容模型</th><td>仅允许在 head 内</td></tr>
<tr><th>允许的父元素</th><td>接受流式内容的元素</td></tr>
<tr><th>闭合标签</th><td>需要 <code></title></code> 标签</td></tr>
<tr><th>状态</th><td><span class="tag-badge badge-stable">标准</span></td></tr>
</tbody></table></div>
<h2 id="syntax">📝 语法</h2>
<pre class="ref-syntax-block"><code class="language-html"><title>页面标题</title></code></pre>
<div class="ref-attr-links">
<a href="/cn/html/reference/global-attributes.html" class="ref-attr-link">查看所有全局属性 →</a>
<a href="/cn/html/reference/event-attributes.html" class="ref-attr-link">查看所有事件属性 →</a>
</div>
<h2 id="example" class="example-heading">▶ 示例</h2>
<p class="tryit-intro">编辑下方代码，在 playground 中查看实时效果：</p>
<div class="tryit-wrapper"><iframe class="tryit-iframe" src="/html/editor.html?lang=zh&mode=playground&embed=1&code=%7B%22html%22%3A%20%22%3C%21--%20%E6%96%87%E6%A1%A3%E6%A0%87%E9%A2%98%20--%3E%5Cn%3Chead%3E%5Cn%20%20%3Cmeta%20charset%3D%5C%22UTF-8%5C%22%3E%5Cn%20%20%3Ctitle%3E%E6%88%91%E7%9A%84%E7%AC%AC%E4%B8%80%E4%B8%AA%E7%BD%91%E9%A1%B5%3C%2Ftitle%3E%5Cn%3C%2Fhead%3E%22%2C%20%22css%22%3A%20%22%22%2C%20%22js%22%3A%20%22%22%7D" sandbox="allow-scripts allow-modals allow-same-origin allow-forms" title="Try It playground"></iframe></div>
<div class="tryit-actions"><a href="javascript:void(0)" class="btn-try" onclick="openEditorModal(this)">▶ 试一试</a></div>
<h2 id="browser-support">🌐 浏览器支持</h2>
<div class="ref-browser-support">
<table class="ref-browser-table">
<thead><tr>
<th class="ref-browser-el">浏览器</th>
<th class="ref-browser-th"><img src="/assets/images/Browser/chrome.svg" alt="Chrome" class="ref-browser-icon"><span class="ref-browser-name">Chrome</span></th>
<th class="ref-browser-th"><img src="/assets/images/Browser/edge.svg" alt="Edge" class="ref-browser-icon"><span class="ref-browser-name">Edge</span></th>
<th class="ref-browser-th"><img src="/assets/images/Browser/firefox.svg" alt="Firefox" class="ref-browser-icon"><span class="ref-browser-name">Firefox</span></th>
<th class="ref-browser-th"><img src="/assets/images/Browser/safari-.svg" alt="Safari" class="ref-browser-icon"><span class="ref-browser-name">Safari</span></th>
<th class="ref-browser-th"><img src="/assets/images/Browser/opera.svg" alt="Opera" class="ref-browser-icon"><span class="ref-browser-name">Opera</span></th>
</tr></thead>
<tbody><tr>
<td class="ref-browser-el"><title></td>
<td class="ref-browser-yes"><span class="ref-check">✓</span> <span class="ref-ver">v1</span></td>
<td class="ref-browser-yes"><span class="ref-check">✓</span> <span class="ref-ver">v12</span></td>
<td class="ref-browser-yes"><span class="ref-check">✓</span> <span class="ref-ver">v1</span></td>
<td class="ref-browser-yes"><span class="ref-check">✓</span> <span class="ref-ver">v1</span></td>
<td class="ref-browser-yes"><span class="ref-check">✓</span> <span class="ref-ver">v1</span></td>
</tr>
<tr><td colspan="6" class="ref-browser-all">所有主流浏览器均支持</td></tr>
</tbody></table>
</div>
<div class="note-box tip"><strong>提示：</strong> title 文字会作为浏览器标签和 SEO 标题，务必简明并含关键词；不能包含其他标签。</div>
<h2 id="related-tags">🏷️ 相关标签</h2>
<div class="related-tags ref-tag-grid">
<a class="ref-tag-card" href="head.html" title="head 元素"><head></a>
<a class="ref-tag-card" href="meta.html" title="meta 元素"><meta></a>
</div>
<h2 id="related-cases">💡 相关案例</h2>
<div class="ref-case-empty">更多案例即将上线，敬请期待。</div>
<h2 id="see-also">📚 相关教程</h2>
<div class="ref-tag-grid">
<a class="ref-tag-card" href="/cn/html/index.html" title="HTML Introduction">HTML Introduction</a>
<a class="ref-tag-card" href="/cn/html/basics.html" title="HTML Basics">HTML Basics</a>
<a class="ref-tag-card" href="/cn/html/elements.html" title="HTML Elements">HTML Elements</a>
</div>
<div class="ref-tutorial-grid">
<a class="ref-tutorial-card" href="/cn/html/reference/">
<div class="ref-tutorial-card-title">HTML 标签参考手册</div>
<div class="ref-tutorial-card-desc">查看全部 HTML 标签的语法、属性与示例。</div>
</a>
</div>
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<h3 id="report-title">🙏 帮我们做得更好</h3>
<!-- 暖文区 -->
<div class="report-welcome" id="report-welcome">
我们是刚上线的编程教程站，几个人的小团队，精力有限。页面虽经检查，难免还有疏漏——链接失效、排版错乱、内容有误、语言生硬……<br><br>
如果您发现了，麻烦告诉我们，我们会在收到反馈后第一时间进行修复，再次感谢您的光临 🙏
</div>
<!-- URL（对用户隐藏，随表单一起提交） -->
<div class="report-page-url" id="report-url-display" style="display:none"></div>
<label id="report-type-label">问题类型</label>
<div class="report-types" id="report-type-tags"></div>
<label id="report-desc-label">问题描述</label>
<textarea class="report-desc" id="report-desc" rows="4" placeholder="请描述一下您遇到的问题……"></textarea>
<!-- 蜜罐 -->
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<script>
/* ── 多语言字典 ── */
var REPORT_LANG = {
'zh-CN': {
welcome: '我们是刚上线的编程教程站，几个人的小团队，精力有限。页面虽经检查，难免还有疏漏——链接失效、排版错乱、内容有误、语言生硬……<br><br>如果您发现了，麻烦告诉我们，我们会在收到反馈后第一时间进行修复，再次感谢您的光临 🙏',
title: '帮我们做得更好',
typeLabel: '问题类型',
descLabel: '问题描述',
descPlaceholder: '请描述一下您遇到的问题……',
submit: '好的，这就提交 🙏',
success: '感谢您！您的反馈已经收到，我们会尽快处理。<br>有您帮忙，这个站一定会越来越好 ❤️',
error: '提交失败了……能再试一次吗？',
types: ['链接失效', '排版错乱', '内容错误', '本地化问题', '其他']
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'en': {
welcome: 'We\'re a tiny team who just launched this tutorial site. We\'ve checked everything, but things still slip through — broken links, layout issues, wrong content, awkward wording…<br><br>If you spot something, let us know and we\'ll get it fixed right away. Thanks for stopping by! 🙏',
title: 'Help Us Improve',
typeLabel: 'Issue Type',
descLabel: 'Description',
descPlaceholder: 'Tell us what you found…',
submit: 'Send it over 🙏',
success: 'Got it! Thank you so much — we\'ll look into it right away.<br>With your help, this site keeps getting better ❤️',
error: 'Something went wrong… Could you try again?',
types: ['Broken Link', 'Layout Issue', 'Content Error', 'Translation', 'Other']
},
'ar': {
welcome: 'نحن فريق صغير أطلقنا هذا الموقع التعليمي حديثاً. راجعنا كل صفحة، لكن قد توجد بعض الأخطاء — روابط معطلة، تخطيط غير صحيح، محتوى خاطئ، ترجمة غير دقيقة…<br><br>إذا لاحظت أي خطأ، فأخبرنا وسنصلحه فوراً. شكراً جزيلاً لمساعدتك لنا! 🙏',
title: 'ساعدنا على التحسين',
typeLabel: 'نوع المشكلة',
descLabel: 'الوصف',
descPlaceholder: 'صِف ما وجدته…',
submit: 'أرسل التقرير 🙏',
success: 'وصلتنا ملاحظاتك! شكراً جزيلاً — سنقوم بمراجعتها فوراً.<br>بمساعدتك، سيصبح هذا الموقع أفضل ❤️',
error: 'حدث خطأ… هل يمكنك المحاولة مرة أخرى؟',
types: ['رابط معطل', 'مشكلة تخطيط', 'خطأ في المحتوى', 'خطأ في الترجمة', 'أخرى']
},
'pt-BR': {
welcome: 'Somos uma equipe pequena e acabamos de lançar este site de tutoriais. Revisamos tudo, mas sempre escapa alguma coisa — links quebrados, layout bagunçado, conteúdo errado, tradução estranha…<br><br>Se você encontrar algo, nos avise e vamos corrigir o mais rápido possível. Valeu pela ajuda! 🙏',
title: 'Nos ajude a melhorar',
typeLabel: 'Tipo de problema',
descLabel: 'Descrição',
descPlaceholder: 'Conte o que você encontrou…',
submit: 'Enviar 🙏',
success: 'Recebemos! Muito obrigado — vamos dar uma olhada.<br>Com sua ajuda, este site fica cada vez melhor ❤️',
error: 'Algo deu errado… Pode tentar novamente?',
types: ['Link quebrado', 'Problema de layout', 'Erro de conteúdo', 'Erro de tradução', 'Outros']
},
'ja': {
welcome: '私たちは少人数のチームで、このチュートリアルサイトを立ち上げたばかりです。念入りに確認していますが、それでも不具合が残っているかもしれません — リンク切れ、レイアウト崩れ、内容の誤り、不自然な翻訳…<br><br>お気づきの点がございましたら、ぜひお知らせください。いただいたご報告はすぐに確認し、修正いたします。どうぞよろしくお願いいたします🙏',
title: 'みなさまのご意見をお聞かせください',
typeLabel: '問題の種類',
descLabel: '詳細',
descPlaceholder: '不具合の内容を詳しく教えてください…',
submit: '送信します 🙏',
success: 'ご報告ありがとうございます！すぐに確認いたします。<br>みなさまのご協力で、このサイトはより良いものに成長していきます ❤️',
error: 'エラーが発生しました…もう一度お試しいただけますか？',
types: ['リンク切れ', 'レイアウト崩れ', '内容の誤り', '翻訳の問題', 'その他']
}
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document.getElementById('report-type-label').textContent = texts.typeLabel;
document.getElementById('report-desc-label').textContent = texts.descLabel;
document.getElementById('report-desc').placeholder = texts.descPlaceholder;
document.getElementById('report-submit-btn').textContent = texts.submit;
// URL
document.getElementById('report-url-display').textContent = window.location.pathname + window.location.search;
// 类型标签
var tagsContainer = document.getElementById('report-type-tags');
tagsContainer.innerHTML = '';
texts.types.forEach(function(t, i) {
var tag = document.createElement('span');
tag.className = 'report-type-tag' + (i === 0 ? ' active' : '');
tag.textContent = t;
tag.dataset.index = i;
tag.onclick = function() {
tagsContainer.querySelectorAll('.report-type-tag').forEach(function(el) { el.classList.remove('active'); });
this.classList.add('active');
};
tagsContainer.appendChild(tag);
});
overlay.classList.add('open');
setTimeout(function() { document.getElementById('report-desc').focus(); }, 300);
}
function closeReportModal(e) {
if (e && e.target !== e.currentTarget && e.target.id !== 'report-modal-overlay' && e.target.className !== 'close-x') {
return;
}
document.getElementById('report-modal-overlay').classList.remove('open');
}
function submitReport() {
var texts = getReportLang();
var btn = document.getElementById('report-submit-btn');
btn.disabled = true;
btn.textContent = '…';
// 蜜罐检测：被机器人填了 → 静默丢弃
if (document.getElementById('report-honeypot').value.trim() !== '') {
showReportResult(true, texts.success);
return;
}
var activeTag = document.querySelector('#report-type-tags .report-type-tag.active');
var typeIndex = activeTag ? parseInt(activeTag.dataset.index) : 0;
var typeText = activeTag ? activeTag.textContent : texts.types[0];
var payload = JSON.stringify({
url: window.location.pathname + window.location.search,
page_lang: (document.documentElement.lang || 'en').trim(),
type_index: typeIndex,
type: typeText,
desc: document.getElementById('report-desc').value.trim()
});
var xhr = new XMLHttpRequest();
xhr.open('POST', '/api/report.php', true);
xhr.setRequestHeader('Content-Type', 'application/json');
xhr.timeout = 10000;
xhr.onload = function() {
if (xhr.status === 200) {
try {
var resp = JSON.parse(xhr.responseText);
showReportResult(resp.ok, resp.ok ? texts.success : (resp.msg || texts.error));
} catch(e) {
showReportResult(true, texts.success);
}
} else {
showReportResult(true, texts.success);
}
};
xhr.onerror = function() {
showReportResult(true, texts.success);
};
xhr.ontimeout = function() {
showReportResult(false, texts.error);
};
xhr.send(payload);
}
function showReportResult(success, msg) {
document.getElementById('report-form-area').style.display = 'none';
var msgArea = document.getElementById('report-msg-area');
msgArea.className = 'report-msg show ' + (success ? 'success' : 'error');
document.getElementById('report-msg-icon').textContent = success ? '🙏' : '😅';
document.getElementById('report-msg-text').innerHTML = msg;
setTimeout(function() {
document.getElementById('report-modal-overlay').classList.remove('open');
}, 4000);
}
// 点击遮罩关闭
document.addEventListener('click', function(e) {
if (e.target.id === 'report-modal-overlay') {
closeReportModal(e);
}
});
</script>
<!-- Load mobile menu script for pages that don't already have it -->
<script>
(function() {
function loadIfNeeded() {
if (document.querySelector('script[src*="tutorial.js"]')) return;
var s = document.createElement('script');
s.src = '/assets/js/tutorial.js';
s.defer = true;
document.body.appendChild(s);
}
if (document.readyState === 'loading') {
document.addEventListener('DOMContentLoaded', loadIfNeeded);
} else {
loadIfNeeded();
}
})();
</script>
</body>
</html>