HTML5 semantics - main

As early as 2013, the 61b85035edf2b42260fdb5632dc5728a element was officially added to the W3C HTML specification. Up to now, the definition of this element has been very complete, so now it is time to take a deeper look at when it is appropriate to use

　W3C specification

　The main purpose of 61b85035edf2b42260fdb5632dc5728a is to map ARIA’s landmark function main to elements in HTML. This helps screen readers and assistive devices know where the main content of the page begins. The W3C specification describes 61b85035edf2b42260fdb5632dc5728a as:

The main content of a document or application. The main content area consists of content that directly relates to or extends to the central topic of the document or the core functionality of the app.

Since the 61b85035edf2b42260fdb5632dc5728a element was included in the HTML specification, the 6c04bd5ca3fcae76e30b72ad730ca86d element has reverted to its definition in HTML4.

The body element represents the content of the document.

Details

One thing to note about using the 61b85035edf2b42260fdb5632dc5728a element is that it can only be used in each page once. Why should we stipulate that a page can only be used once? Although I'm not interested in the specific details, some of the points seem to make sense.

According to the specification, if you try to use multiple 61b85035edf2b42260fdb5632dc5728a tags in a document, the W3C validator will throw an error.

Another requirement for the 61b85035edf2b42260fdb5632dc5728a element is that it cannot be used as a child element node of 23c3de37f2f9ebcb477c4a90aac6fffd, 1aa9e5d373740b65a0cc8f0a02150c53, 15221ee8cba27fc1d7a26c47a001eb9b, c37f8231a37e88427e62669260f0074d, c787b9a589a3ece771e842a6176cf8e9.

Use

Just like other new HTML5 elements, not all browsers can recognize 61b85035edf2b42260fdb5632dc5728a and add preset styles to it. You may need to Make it a block-level element in its own CSS file.

main {display:block;}

Sometimes, in order to support some lower versions of IE browsers, you may also need to use JavaScript to create this element.

<script type="text/javascript">document.createElement(&#39;main&#39;);</script>

Of course, you can also use html5shiv.

The easiest way to use the 61b85035edf2b42260fdb5632dc5728a element is to replace the ID or Class value with main or content. dc6dce4a544fdca2df29d5ac0ea9906b element.

So, what should it look like in practice? Below is the structure of the document before using the 61b85035edf2b42260fdb5632dc5728a element.

<header>Header</header>
    <div id="content">Main Content</div>
    <footer>Footer</footer>

The following uses the 61b85035edf2b42260fdb5632dc5728a element to rewrite the document.

  <header>Header</header>
    <main id="content">Main Content</main>
    <footer>Footer</footer>

Okay, this is so simple that in less than a minute we can rewrite the document into the latest HTML5 style.

Summary

As you can see, using the 61b85035edf2b42260fdb5632dc5728a element is super easy and only takes a few minutes, so now it’s really time to bring in the 61b85035edf2b42260fdb5632dc5728a It’s time for website development.

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