JavaScript Dom_1 Introductory Introduction

1. The file object model, or DOM, is the standard programming interface recommended by the Organization for the processing of extensible flag languages. The Document Object model dates back to the late 1990 's "browser Wars" between Microsoft and Netscape, which gave the browser powerful features in order to make life and death in JavaScript and JScript. Microsoft has added a number of proprietary things to Web technology, including VBScript, ActiveX, and Microsoft's own DHTML format, making it impossible for many Web pages to be displayed using non-Microsoft platforms and browsers. Dom is the masterpiece of the time.

   
   

2. Dom= Document Object Model, which provides a platform-and language-independent way to access and modify the content and structure of a document. In other words, this is a common way of representing and working with an HTML or XML document. A little

   Dom is important, Dom is designed to be based on the Object Management Organization (OMG) protocol, so it can be used in any programming language. It was originally thought of as a way to allow JavaScript to be portable between browsers, but Dom's application has gone far beyond this range. Dom technology allows the user page to dynamically change, such as the ability to dynamically display or hide an element, change their properties, add an element, and so on, Dom technology makes the page interactivity greatly enhanced. [1]

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

3. Dom Description

Document Object model, DOM manipulation is a tree-based API for xml/html.

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Advantages and Disadvantages

The advantages of DOM are mainly shown in:

Easy to use, when using the DOM, all the XML document information will be stored in memory, and the traversal is simple, support XPath, enhance the ease of use.

The disadvantages of Dom are mainly manifested in:

Low efficiency, slow parsing, high memory consumption, and almost impossible to use for large files. In addition, low efficiency also manifests itself in a significant amount of time spent, because when parsing using the DOM, an object is created for each element, attribute, processing-instruction, and comment of the document. Thus, the creation and destruction of a large number of objects used in the DOM mechanism will undoubtedly affect their efficiency.

From the Baidu Encyclopedia.

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JavaScript Dom_1 Introductory Introduction