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How to parse html%%

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2023-05-15 18:53:37605browse

HTML is a markup language used to create the structure of web pages. It provides a way to mark up text, images, links, and other website-related content. HTML can insert various elements into web pages, including tables, lists, images, tables, and more. This article will discuss the HTML parsing process and how to write effective HTML code.

Parsing of HTML

HTML parser is a program used to convert HTML code into web pages. When a browser processes a web page, it reads the HTML code and converts it into a visual web page. This process can be divided into the following steps:

  1. Word segmentation of HTML strings: First, the HTML code is divided into parts called words. These words represent the elements (tags) and text of HTML. For example, the tag "h1" is one word and "Welcome to my website!" is another word.
  2. Build a DOM tree: The DOM tree is a tree structure that represents the parent-child relationship between HTML elements. When the parser reads the HTML code, it creates a node for each HTML element and builds a DOM tree based on their parent-child relationships. The DOM tree takes the HTML document itself as the root node and contains all HTML elements.
  3. Processing CSS and JavaScript code: CSS and JavaScript code are used to control the style and behavior of web pages. Browser parsers combine CSS and JavaScript code with the DOM tree to make them valid. For example, CSS code can control the color, font, size, and position of text and other elements through style sheets.
  4. Rendering the web page: Finally, the browser merges the DOM tree and CSS styles, and then renders the web page on the screen. This process includes converting HTML elements into actual visual attributes such as height, width, and color.

Writing effective HTML code

Writing effective HTML code not only makes the page easier to parse and render, but also improves the performance and accessibility of the page. Here are a few tips for writing effective HTML code:

  1. Use semantic markup: Semantic HTML markup tells the browser what each section on the page represents. This helps improve accessibility, SEO, and code readability. For example, use "h1" tags to tag page titles, and "ul" and "li" tags to create lists.
  2. Avoid redundant tags: Use as few HTML tags as possible to implement the page. Avoid using tables and other complex markup and use only necessary markup to define text and images. This helps reduce page file size and improve page loading speed.
  3. Use valid HTML structure: Use valid HTML structure and follow the standard HTML specification. This ensures that the page renders consistently across different browsers.
  4. Use alt attribute: When inserting pictures, be sure to add the "alt" attribute to each image. This improves the accessibility of the page and helps search engines better understand the page content.

Summary

HTML parser converts HTML code into visual web pages. Writing effective HTML code improves page performance, accessibility, and readability. Complying with HTML specifications and using semantic markup ensures that pages are rendered in a consistent manner across different browsers, while ensuring that web pages are readable and accessible.

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