Detailed explanation and best practices of HTML5 block elements: Building a semantic and highly accessible website
HTML5 provides powerful block elements, such as<nav></nav>
,<aside></aside>
,<article></article>
and<section></section>
, used to build a semantic website structure.<main></main>
Elements also play an important role, representing the main content area of ??the page. This article will explore the usage of these elements in depth and focus on how to build a highly accessible website structure.
<nav></nav>
The element is equivalent to role="navigation"
and is used for the main navigation area and is often seen frequently throughout the website. This includes primary navigation, secondary navigation and in-page navigation.
<aside></aside>
Elements are equivalent to role="complementary"
and are used for supplementary information that is less relevant to the main content, such as sidebars, comments in articles, or lists of articles related to the bottom of a blog post.
<article></article>
Elements are equivalent to role="article"
and are used to represent independent, self-contained content, such as widgets, blog posts, or comments in blog posts.
<section></section>
Elements are equivalent to role="region"
and are used to represent common content that requires the parent block element to provide additional context to understand its meaning. You can use it when other semantic elements are not applicable<section></section>
.
Important Note: Some technologies may affect the experience of screen reader users. We will continue to update our articles to ensure the best information is provided.
Article Directory
For your convenience, here is a list of all titles of the article:
Table of contents
-
<nav></nav>
Best practices for elements- Search forms without using
<nav></nav>
pack - Avoid using "nav" or "navigation" in the tag
- Self-checking problems
-
<nav></nav>
Don't always have to link lists
- Search forms without using
Avoid nesting
<aside></aside>
element-
<article></article>
The element is similar to a "block",<section></section>
Elements are similar to "elements"- Comment area
Don't use it
Replace block elements- Header and footer
- Header content
- Footer content
- Block Elements and Document Outline Algorithm
- Currently, the browser does not support document outline algorithm
- Content chunking
-
<main></main>
element - Adding tags to block elements: Three ways
- Method 1: Use
aria-label
attribute - Method 2: Add
<h1> arrive<code><h6 id="element"> element</h6>
- Method 3: Use
aria-labelledby
attribute
- Method 1: Use
- Only one label method is used for each block element
- Add block tags to the sample layout
- Set the first title as the first title
- Concerns about simplifying document outline algorithm specifications
- Use ARIA attributes in sample layout block elements
- Use
aria-label
- Using
aria-labelledby
- Results using ARIA properties
- Use
- How to deal with it
<h1> arrive<code><h6 id="Title-level-outside"> Title level outside</h6>
- Check whether the website structure is reasonable
- Download and use a screen reader
The article is detailed and has a long time. It is recommended that you collect it for future reference.
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... (There are a large number of code examples and detailed explanations in the original text here, and the core concepts and conclusions are preserved) ...
In short, using HTML5 block elements and ARIA attributes rationally and following the principles of document outline algorithms can build websites with clear semantics, reasonable structure and strong accessibility, which can improve user experience, which is especially crucial for screen reader users. It is recommended that you download and use a screen reader to test it to make sure your website is friendly to all users.
- Header and footer
The above is the detailed content of How to Section Your HTML. For more information, please follow other related articles on the PHP Chinese website!

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