With the continuous development and popularization of Internet technology, more and more people are beginning to learn and use front-end development technology, and the two important tools involved are JavaScript and CSS. When writing code in these two languages, comments have become an essential part in order to allow yourself and others to better understand the code. This article will introduce the relevant knowledge of JavaScript and CSS annotations in detail to help readers understand the annotation specifications and usage of these two languages more clearly.
1. JavaScript Notes
JavaScript is an object- and event-driven programming language that is widely used in web development, game development and other fields. There are two main comment formats in JavaScript: single-line comments and multi-line comments.
- Single-line comments
Single-line comments start with "//" and are used to explain the specific role or purpose of a line in the code, which makes it easier for us to locate in the code. and understanding. For example:
// 这是一个单行注释 var count = 10; // 这个变量表示数量为10
- Multi-line comments
Multi-line comments are wrapped with "/ /" and are used to comment multiple lines of content in the code . For example:
/* 这是一个多行 注释 */ /* 这是一个包含示例代码的多行注释, 可以帮助读者更好地了解代码的运行过程 var num = 10; alert(num); */
When actually writing JavaScript code, single-line comments and multi-line comments are usually mixed to achieve better comment effects.
2. CSS comments
CSS is a language used for web page layout and style design. Comments are also needed to improve the readability and maintainability of the code. There are also two CSS comment formats: single-line comments and multi-line comments.
- Single-line comments
CSS single-line comments start with "//" and are used to explain the specific function or purpose of a line in the code, which can facilitate us in the code Orientation and understanding. For example:
/* 这是一个单行注释 */ body { font-size: 14px; // 设置字体大小为14px }
- Multi-line comments
CSS multi-line comments are wrapped with "/ /" and are used to comment multiple lines in the code content. For example:
/* 这是一个多行 注释 */ body { font-size: 14px; /* 这里可以加入具体的代码注释 */ }
In CSS files, comments are often used to mark specific styles or provide useful information when collaborating. Through comments, we can more clearly understand the function and use of the code.
3. Best practices for comments
Whether it is JavaScript or CSS, comments are a very important part when writing code. When making comments, we should follow the following best practices:
- Write comments in concise and clear language to describe the function or purpose achieved by the code.
- Mark clearly where comments are needed, and don’t stick to the number of comments.
- Avoid repeated comments in the code and reduce redundancy.
- Pay attention to code quality and readability, and try not to have errors or misspelled comments.
- The content of comments should be updated at any time as the code is modified to ensure that comments and code are consistent.
In short, commenting is a very important task. We should develop a good habit of commenting code frequently, which is very necessary for our development work.
The above is the detailed content of js css annotation. For more information, please follow other related articles on the PHP Chinese website!

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