Document Object Model (DOM)

Official definition of DOM

• DOM, Document Object Model, Document Object Model. We can think of all "things" in a web page as "objects".

• DOM is a web page standard or rule set by the W3C, and this standard is implemented in the form of an "object" in the browser.

• The official definition of DOM: DOM enables scripts, dynamic access or operations, web page content, web page appearance, and web page structure.

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# Classification of DOM

• Core DOM: Provides common properties and methods for manipulating HTML documents and XML documents at the same time.

• HTML DOM: Special attribute method provided for HTML documents.

• XML DOM: Special properties and methods provided for XML documents.

• CSS DOM: Provides properties and methods for operating CSS.

• Event DOM: Event Object Model. Such as: onclick, onload, etc.

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##HTML node tree

     
   
 
 
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##Node relationship

Root node, an HTML document has only one root, which is the HTML node.

• Subnode: the subordinate node of a certain node.

• Parent node: the superior node of a certain node.

• Sibling node: Two child nodes belong to the same parent node.

#Node type in DOM

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The document document node represents the entire web page and does not represent any HTML tags. But it is the parent node of the html node.

• element element node refers to any HTML tag. Each HTML tag is called an "element node". It can have text nodes and attribute nodes.

• attribute attribute node. Refers to the attributes of HTML tags.

• text node. Is the bottom node of the node tree.