: Define the main content of the table
<tfoot> tags in HTML tables are used to semantically divide table structures. 1. <thead> defines the table header, including the column title , which facilitates fixing the table header, printing control and style settings; 2.
<tbody> wraps data rows, improves readability and supports JavaScript operation data; 3.
<tfoot> is used to summarize information at the bottom, and even if the code is in front, it will be rendered by the browser at the bottom of the table, which helps load the footnote content first. 
<thead> , <code><tbody> and <code><tfoot> tags in the HTML table structure are used to semantically divide different parts of the table. They themselves do not directly affect the appearance of the table, but can improve code readability, enhance semantic expression, and optimize the display and accessibility of the table in some scenarios. <img src="/static/imghw/default1.png" data-src="https://img.php.cn/upload/article/000/000/000/175251450521251.jpeg" class="lazy" alt="What are <thead>, <tbody>, and <tfoot> used for?"> ,</tfoot>
<tbody> , and</tbody>
<tfoot> used for?" /><h2> <code><thead> : defines the table header part of the table<p> This tag is used to wrap the part of the table that represents the "column title". Usually it contains one or more <code><tr> (table rows), and each <code><tr> contains several <code><th> (table header cells).<p> for example: </p>
<img src="/static/imghw/default1.png" data-src="https://img.php.cn/upload/article/000/000/000/175251450625128.jpeg" class="lazy" alt="What are <thead>, <tbody>, and <tfoot> used for?"> ,</th>
<tbody> , and</tbody>
<tfoot> used for?" /><pre class='brush:php;toolbar:false;'> <head>
<tr>
<th>Name</th>
<th>Age</th>
<th>City</th>
</tr>
</head></pre><p> The advantage of using <code><thead>
is that the browser can identify which content is the header, which is convenient for fixing the header, printing control and other processing. It is also convenient to use CSS to set the header style separately, or use JavaScript to manipulate the header content.
<tbody>
: Define the main content of the table
This part is the "data area" of the table, which contains most of the data rows that are actually displayed. It should be placed after <thead>
(if any), and there can be multiple <tbody>
, for example to group and display different categories of data.
,<tbody> , and<tfoot> used for?" /> Common writing methods are as follows:
<tbody>
<tr>
<td>Zhang San</td>
<td>28</td>
<td>Beijing</td>
</tr>
<tr>
<td>Li Si</td>
<td>34</td>
<td>Shanghai</td>
</tr>
</tbody>
Using <tbody>
can make the table structure clearer and facilitate batch manipulation of data rows through JavaScript, such as sorting, filtering, highlighting the current row, etc.
<tfoot>
: define the bottom summary information of the table
If you want to display totals, averages, or other summary information at the bottom of the table, you can wrap these contents with <tfoot>
. It usually follows <thead>
and <tbody>
.
Example:
<tfoot>
<tr>
<td>Total</td>
<td>62</td>
<td></td>
</tr>
</tfoot>
Although the visual content of <tfoot> will appear at the bottom of the table, in HTML code, you can also put it at the beginning of the table, and the browser will still automatically render it at the bottom. This feature may be useful when you need to load the footnote content first.
In general, using these three tags reasonably can make the table structure clearer and have stronger semantics, and can also achieve more functions in conjunction with CSS and JavaScript.
Basically that's it.
The above is the detailed content of What are , , and used for?. For more information, please follow other related articles on the PHP Chinese website!

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