如何将HTML转换为HTML5?

HTML5是HTML标准的第五个主要版本，是用于构建和呈现互联网内容的核心技术之一。相对于之前的HTML版本，HTML5引入了许多新特性和改进，使得开发者能够创建更丰富、更强大的Web应用和内容。

一、HTML4迁移至HTML5

接下来为大家演示如何把 HTML4 页面在不破坏如何原始内容和结构的情况下转换为 HTML5 页面。XHTML 迁移至 HTML5也可以使用相同的技巧。

HTML 4	HTML 5
<div id=”header”>	<header>
<div id=”menu”>	<nav>
<div id=”content”>	<section>
<div id=”post”>	<article>
<div id=”footer”>	<footer>

二、HTML4页面

以下是一个典型的HTML4页面：

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
"http://www.w3.org/TR/html4/loose.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
<title>HTML4</title>
<style>
body {font-family:Verdana,sans-serif;font-size:0.8em;}
div#header,div#footer,div#content,div#post 
{border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;}
div#header,div#footer {color:white;background-color:#444;margin-bottom:5px;}
div#content {background-color:#ddd;}
div#menu ul {margin:0;padding:0;}
div#menu ul li {display:inline; margin:5px;}
</style>
</head>
<body>
<div id="header">
<h1>Monday Times</h1>
</div>
<div id="menu">
<ul>
<li>News</li>
<li>Sports</li>
<li>Weather</li>
</ul>
</div>
<div id="content">
<h2>News Section</h2>
<div id="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
</div>
<div id="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
</div>
</div>
<div id="footer">
<p>&copy; 2014 Monday Times. All rights reserved.</p>
</div>
</body>
</html>

三、更改为HTML5声明

修改文档类型，从 HTML4 声明：

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
"http://www.w3.org/TR/html4/loose.dtd">

修改为 HTML5 声明：

<!DOCTYPE html>

四、更改为HTML5编码

修改编码信息，从 HTML4：

<meta http-equiv="Content-Type" content="text/html;charset=utf-8">

改为 HTML5：

<meta charset="utf-8">

五、添加shiv

所有现代浏览器都支持 HTML5 语义元素。此外，可以“教授”老式浏览器如何处理“未知元素”。

为 Internet Explorer 支持而添加的 shiv：

<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->

注意：请在《HTML5浏览器支持》中阅读更多有关 shiv 的知识。

六、HTML5添加CSS

请看已有的 CSS 样式：

div#header,div#footer,div#content,div#post {
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
div#header,div#footer {
color:white;background-color:#444;margin-bottom:5px;
}
div#content {
background-color:#ddd;
}
div#menu ul {
margin:0;padding:0;
}
div#menu ul li {
display:inline; margin:5px;
}
Duplicate with equal CSS styles for HTML5 semantic elements:
header,footer,section,article {
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
header,footer {
color:white;background-color:#444;margin-bottom:5px;
}
section {
background-color:#ddd;
}
nav ul {
margin:0;padding:0;
}
nav ul li {
display:inline; margin:5px;
}

七、更改header/footer

把 id=”header” 和 id=”footer” 的 <div> 元素：

<div id="header">
<h1>Monday Times</h1>
</div>
.
.
.
<div id="footer">
<p>&copy; 2016 zzbaike. All rights reserved.</p>
</div>

修改为 HTML5 语义元素 <header> 和 <footer>：

<header>
<h1>Monday Times</h1>
</header>
.
.
.
<footer>
<p>© 2016 zzbaike. All rights reserved.</p>
</footer>

八、更改为HTML5 nav

把 id=”menu” 的 <div> 元素：

<div id="menu">
<ul>
<li>News</li>
<li>Sports</a></li>
<li>Weather</li>
</ul>
</div>

修改为 HTML5 语义元素 <nav>：

<nav>
<ul>
<li>News</li>
<li>Sports</a></li>
<li>Weather</li>
</ul>
</nav>

九、更改为HTML5 section

把 id=”content” 的 the <div> 元素：

<div id="content">
.
.
.
</div>

修改为 HTML5 语义元素 <section>：

<section>
.
.
.
</section>

十、更改为HTML5 article

把 class=”post” 的所有 <div> 元素：

<div class="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
</div>

修改为 HTML5 语义元素 <article>：

<article>
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
</article>

删除这些“不再需要的”样式：

div#header,div#footer,div#content,div#post {
border:1px solid grey;margin:5px;margin-bottom:15px;padding:8px;background-color:white;
}
div#header,div#footer {
color:white;background-color:#444;margin-bottom:5px;
}
div#content {
background-color:#ddd;
}
div#menu ul {
margin:0;padding:0;
}
div#menu ul li {
display:inline; margin:5px;
}

十一、HTML5页面

最后可以删除 <head> 标签。HTML5 中不再需要它们：

<!DOCTYPE html>
<html lang="en">
<title>HTML5</title>
<meta charset="utf-8">
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js">
</script>
<![endif]-->
<style>
body {
font-family:Verdana,sans-serif;font-size:0.8em;
}
header,footer,section,article {
border:1px solid grey;
margin:5px;margin-bottom:15px;padding:8px;
background-color:white;
}
header,footer {
color:white;background-color:#444;margin-bottom:5px;
}
section {
background-color:#ddd;
}
nav ul {
margin:0;padding:0;
}
nav ul li {
display:inline; margin:5px;
}
</style>
<body>
<header>
<h1>Monday Times</h1>
</header>
<nav>
<ul>
<li>News</li>
<li>Sports</li>
<li>Weather</li>
</ul>
</nav>
<section>
<h2>News Section</h2>
<div id="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
</div>
<div id="post">
<h2>News Article</h2>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
<p>Ipsum lurum hurum turum ipsum lurum hurum turum ipsum lurum hurum turum ipsum 
lurum hurum turum.</p>
</div>
</section>
<footer>
<p>&copy; 2014 Monday Times. All rights reserved.</p>
</footer>
</body>
</html>

十二、article/section/div差异

在 HTML5 标准中，<article> <section> 与 <div> 之间的差异很小，<section> 元素被定位为相关元素的块；<article> 元素被定义为相关元素的完整的自包含块；<div> 元素被定义为子元素的块。

在上面的例子中，我们曾使用 <section> 作为相关 <articles> 的容器。但是也能够把 <article> 用作文章的容器。

下面是一些不同的例子：

<article> 中的 <article>：
<article>
<h2>Famous Cities</h2>
<article>
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</article>
<article>
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</article>
<article>
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</article>
</article>

<article> 中的 <div>：
<article>
<h2>Famous Cities</h2>
<div class="city">
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="city">
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="city">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</article>

<article> 中的 <section> 中的 <div>：
<article>
<section>
<h2>Famous Cities</h2>
<div class="city">
<h2>London</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="city">
<h2>Paris</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="city">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</section>
<section>
<h2>Famous Countries</h2>
<div class="country">
<h2>England</h2>
<p>London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.</p>
</div>
<div class="country">
<h2>France</h2>
<p>Paris is the capital and most populous city of France.</p>
</div>
<div class="country">
<h2>Japan</h2>
<p>Tokyo is the capital of Japan, the center of the Greater Tokyo Area,
and the most populous metropolitan area in the world.</p>
</div>
</section>
</article>