html5 comment tag is "<!-- -->", everything between "<!--" and "-->" will be regarded as a comment, the syntax "< ;!-- Comment content -->”; Comments are also part of the code, but the browser will automatically ignore the content of the comments, so users cannot see the comments on the web page. Comments can appear anywhere in an HTML document, including at the beginning of the document, at the end of the document, in the middle of the document, outside the tag, within the tag content, etc.
The operating environment of this tutorial: Windows 7 system, HTML5 version, Dell G3 computer.
HTML comments are mainly used to explain the code in the document. Comments are also part of the code, but the browser will automatically ignore the content of the comments, so users cannot see the comments on the web page. .
We should make good use of comments when writing code, because a complete HTML document often consists of hundreds or thousands of lines of code, and it may take a long time when we want to modify a certain part of it. Only then can you find the place you want to modify. With comments, it's different. We can divide the program into several parts according to functions or other conditions and mark them with comments. This can help you and others read your code and improve the readability of the code.
Single line comments
In HTML you can use <!-- -->In code To add a comment, everything between <!-- and --> will be considered a comment. The sample code is as follows:
<!DOCTYPE html>
<html>
<!-- head 开始 -->
<head>
<meta charset="UTF-8"> <!-- 当前文档采用UTF-8编码 -->
<title>HTML注释的写法</title>
</head>
<!-- head 结束 -->
<!-- body 开始 -->
<body>
<!-- 一段文本 -->
<p>欢迎来到php中文网学习HTML教程，请记住地址：https://www.php.cn/</p>
</body>
<!-- body 结束 -->
</html>The running result is as follows:
Comments can appear anywhere in the HTML document, including the beginning of the document, the end of the document, and Middle, outside label, label content, medium.
Multi-line comments
We mainly demonstrated single-line comments earlier, but multi-line comments are also supported in HTML. The difference between multi-line comments and single-line comments is not big. We only need to ensure that the content of the comment is between <!-- and -->, as shown below ：
<!--
多行注释
-->In addition to explaining the code, comments can also be used to annotate the code in the program. For example, when you don’t want a certain piece of code to be executed, you can comment it out first, so that the browser can This code will not be executed.
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