html and escape

HTML and escaping

HTML is a markup language used to create web pages. In HTML, some characters have special meanings, such as the less-than sign (<) and the greater-than sign (>), which are used to define tags, while the & symbol is used to define special characters and entities, such as spaces and copyright symbols. In HTML, these characters need to be escaped in order to be displayed correctly in the web page.

What is HTML escaping?

HTML escaping is the process of converting some characters that have special meanings in HTML into their equivalent representations. For example, if you want to display the less than sign (<) and greater than sign (>) in a Web page instead of defining new tags, you need to use their escape codes. In HTML, these escape codes appear in the form of entity name; or entity value; and are interpreted as escape characters.

Types of HTML escape characters

The HTML standard defines a series of escape characters, which are divided into two categories: named entities and numeric entities.

1. Named entities

Named entities refer to entity names starting with & and ending with;. Some common named entities are listed below:

• < : less than sign (<)
• > : greater than sign (>)
• & : & symbol (&)
• " : Double quotation mark (")
• ' : Single quotation mark (')
• : Space

2. Digital entity

Digital entity refers to the representation of ASCII value starting with and ending with;. Some common numeric entities are listed below:

• & : & symbol (&)
• ": Double quotation mark (")
• ': Single quotation mark (')
• : Space

Why use HTML escaping?

When writing HTML code, characters such as the less than sign (<), greater than sign (>) and & have special meanings. If they are used directly in the HTML code, they will be interpreted as HTML tags by the browser. instead of text. This will cause the browser to be unable to display the web page correctly and may lead to security issues, such as script injection attacks. Therefore, using HTML escape characters can avoid these problems to ensure that web pages are displayed correctly and safely.

How to use HTML escape characters?

HTML escape characters can be used anywhere in HTML code. Here are some examples of using HTML escape characters:

• Less-than sign: If you want to display a less-than sign in a web page, use < or <.
• Greater than sign: If you want to display the greater than sign on the web page, please use > or >.
• & symbol: If you want to display the ampersand symbol in a web page, please use & or &.
• Quotation marks: If you want to display quotation marks in the web page, please use "or".
• Single quotes: If you want to display single quotes in the web page, please use 'or'.
• Space: If you want to display spaces in the web page, please use or .

Summary

In HTML, it is very important to use escape characters because they ensure that web pages are displayed correctly and safely. When using HTML code, be careful not to use characters with special meanings such as the less than sign (<), greater than sign (>), and &. If you need to display these characters in a web page, use the corresponding HTML escape characters.

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