HTML language is a standardized markup language for creating web pages. It uses a series of tags to describe the content and structure of the page. When using HTML language, people often use the two symbols "." and "...". These two symbols look similar, but in fact they have very different meanings. Below, I will introduce the meaning and difference between "." and "..." in detail.
- The meaning and usage of "."
"." is a common symbol, which is mainly used to represent the path of a file. For example, if you need to open the folder "myfolder" in the C drive, you can use the following path: "C:myfolder". In this path, "." represents the current folder, that is, this path is the current folder (myfolder) under the C drive.
In addition, "." also has its own uses in the HTML language. In HTML, "." is usually used to represent class names or tag names. As shown in the following code:
<div class="wrapper"> <p class="text-paragraph">这是一个段落。</p> </div>
In this code, ".wrapper" and ".text-paragraph" are the class names. The dot is the symbol used to represent the class name, so that we can style these classes through CSS, such as modifying their fonts, colors, etc.
- The meaning and usage of "..."
"..." is another symbol used to represent a path. It is usually used to represent the upper-level directory of a folder. . For example, there is a subdirectory named "test" in the folder "myfolder". If you need to jump to this subdirectory, you can use the following path: "C:myfolder..\test". In this path, "..\" is the symbol used to represent the upper-level directory, that is, we jump to the "myfolder" under the C drive, and then jump to the "test" folder.
In HTML language, "..." is usually used to represent the parent element, that is, all elements that contain a certain element. For example, the following code contains two levels of element nesting:
<div class="wrapper"> <p class="text-paragraph">这是一个段落。</p> </div>
In this code, the "div" tag contains the "p" tag, and you can use "..." to represent the "div" element . As shown below:
.text-paragraph {...} .wrapper > ... {...}
In this code, the ".text-paragraph" selector is applied to the "p" tag, while the ".wrapper > ..." selector is applied to its parent element, "div" tag. In this way, we can use CSS to control the style of all child elements in the "wrapper" element (including the "p" tag).
Summary:
To sum up, "." and "..." are symbols used when representing paths or element levels, but they have different meanings and usages. If we want to represent the current path or the element it is in, we can use ".". If we want to represent the previous path or parent element, we can use "...". The same is true in HTML language. If we want to represent a class name, we can use ".". If we want to represent a parent element, we can use "...". Mastering their meaning and usage can make us more proficient in using HTML language and CSS styles.
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