Shulou(Shulou.com)06/02 Report--

This article will explain in detail how to understand the usage of the W3C DOM model. The content of the article is of high quality, so the editor shares it for you as a reference. I hope you will have some understanding of the relevant knowledge after reading this article.

Here we will focus on the DOM model, which is actually an object model described in an object-oriented way. The DOM model defines the objects required to represent and modify a document, their behavior and properties, and the relationships between these objects.

W3C DOM

DOM=DocumentObjectModel, document object model, DOM model can access and modify the content and structure of a document in a platform-and language-independent way. In other words, this is a common way to represent and process an HTML or XML document. It is important that the design of the DOM model is based on the specification of the object Management Organization (OMG), so it can be used in any programming language. At first, it was thought of as a way to make JavaScript portable between browsers, but the application of the DOM model has gone far beyond that.

The DOM model is actually an object model described in an object-oriented way. The DOM model defines the objects required to represent and modify a document, their behavior and properties, and the relationships between these objects. You can think of the DOM model as a tree representation of the data and structure on the page, but the page may not be implemented in such a tree way.

DOM model

According to the W3C DOM model specification, the DOM model is the application programming interface (API) between HTML and XML, and the DOM model maps the entire page to a file composed of hierarchical nodes. There are three levels: level 1, level 2 and level 3.

The level 1 DOM model became the proposal of the W3C in October 1998, which consists of two modules: the core of the DOM model and the HTML of the DOM model. The core of the DOM model can map the XML-based document structure, allowing you to get and manipulate any part of the document. The DOM model HTML extends the core of the DOM model by adding HTML-specific objects and functions.

In view of the fact that the first-level DOM model only aims to map the document structure, the second-level DOM model is broader. By extending the original DOM model, the level 2 DOM model adds support for mouse and user interface events (DHTML supports mouse and user interface events for a long time), scope, traversal (repeated execution of DOM model documents) and cascading style sheets (CSS) through the object interface. The core of DOM Model 1 is also extended to support XML namespaces.

The level 2 DOM model introduces several new DOM model modules to handle new interface types:

DOM view: describes the interface for tracking various views of a document (before and after designing a document using CSS style)

DOM events: describe the event interface

DOM style: describes interfaces that are based on CSS style

DOM traversal and scope: describes the interface for traversing and manipulating document trees

The 3-level DOM model further extends the DOM model by introducing a unified way to load and save documents and document verification methods. DOM model 3 contains a new module called "DOM model loading and saving". The core of the DOM model can support all the contents of XML1.0, including XMLInfoset, XPath, and XMLBase.

So much for sharing about how to understand the usage of the W3C DOM model. I hope the above content can help you and learn more. If you think the article is good, you can share it for more people to see.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.