Table of Contents
Parsing host objects in js
This article mainly introduces the analysis of host objects in js, which has certain reference value. Now I share it with everyone. Friends in need can refer to it.
Host objects are objects provided by the browser. , mainly including DOM objects and BOM objects.
1. Origin of DOM
1.SGML, XML and XHTML
<span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">SGML(标准通用标记语言)是定义使用标签来表示数据的标记语言的语法。<br> - 标签由一个小于号和一个大于号之间的文本组成，如<title><br> - 标签分为起始标签和结束标签，分别表示一个特定区域的开始和这个特定区域的结束，如<title>标题</title><br> - 特性是定义在起始标签内的值。如<img src="pircutre.jpg">，src就是其特性<br>HTML遵循SGML标记语言的语法,它是的SGML一种应用。或者说，SGML用来定义HTML的文档类型定义(DTD)。SGML还用来编写XML的DTD。</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
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<span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">XML对SGML的语法做了更细致和严谨的扩展。<br> - SGML的奇怪语法:<br> - 某些标签不语序出现结束标签，如HTML中的<img>标签，否则会出现错误。<br> - 某些标签的结束标签可以不写，如HTML中的<p>标签。<br> - 标签可以以任何顺序嵌套，如<p><span></p></span>。<br> - 某些特性必须包含值，如<img src="picture.jpg">。<br> - 某些特性不要求一定有值，如<td nowrap>。<br> - 定义特性的两边有没有加双引号都是可以的，如<img src=picture.jpg>也是允许的。<br> - XML去掉了许多SGML中的随意语法，并且规定了新的语法:<br> - 任何的起始标签都必须有一个结束标签。<br> - 可以采用另一种简化语法，即一个标签同时表示起始标签和结束标签，即<tag />，如<br />,<hr />。<br> - 标签必须按合适的顺序嵌套。就近原则书写结束标签。<br> - 所有的特性都必须有值。<br> - 所有的特性都必须在值得周围加上双引号。<br>XML衍生出了MathML、SVG、RDF、RSS等等。同时，HTML被改进为XHML，即遵循XML语法的HTML。XHMTL被称为严格模式。</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
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2.XML API
<span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">XML定义了HTML的数据排版和解析方式。根据XML语言规范，需要制定API来实现对<span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">这些数据的操作和访问。<br>DOM模型就是最为流行的针对XML的基于树的API。它将XML解析为一颗有节点的树模型，并使用一系列互相关联的对象来表示XML的代码。从而能够指导开发增删改查等具体API的实现。<br>* DOM是语言无关的API，它并不与其它语言绑定。但对于JavaScript而言，DOM被习惯理解成API集合。</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
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<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;">HTML DOM <span style="color: #808080; font-family: 'Menlo';">（文档对象模型）<br><span style="color: #808080; font-family: 'Menlo';"> - 当网页被加载时，浏览器会创建页面的文档对象模型（<span style="color: #808080;">Document Object Model<span style="color: #808080; font-family: 'Menlo';">）。<span style="color: #808080;"><br><span style="color: #808080;"> - HTML DOM <span style="color: #808080; font-family: 'Menlo';">模型被构造为对象的树。<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">通过<span style="color: #808080;"> HTML DOM<span style="color: #808080; font-family: 'Menlo';">，可访问<span style="color: #808080;"> HTML <span style="color: #808080; font-family: 'Menlo';">文档的所有元素。<span style="color: #808080;"><br><span style="color: #808080;"> - <html><br><span style="color: #808080;"> <head><br><span style="color: #808080;"> <title>...</title><br><span style="color: #808080;"> ...<br><span style="color: #808080;"> </head><br><span style="color: #808080;"> <body><br><span style="color: #808080;"> <p><br><span style="color: #808080;"> ...<br><span style="color: #808080;"> </p><br><span style="color: #808080;"> ...<br><span style="color: #808080;"> </body><br><span style="color: #808080;"> </html><br> - <span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">通过可编程的文档对象模型，<span style="color: #808080;">JavaScript <span style="color: #808080; font-family: 'Menlo';">获得了足够的能力来创建动态的<span style="color: #808080;"> HTML<span style="color: #808080; font-family: 'Menlo';">。<span style="color: #808080;"><br><span style="color: #808080;"> - JavaScript <span style="color: #808080; font-family: 'Menlo';">能够改变页面中的所有<span style="color: #808080;"> HTML <span style="color: #808080; font-family: 'Menlo';">元素<span style="color: #808080;"><br><span style="color: #808080;"> - JavaScript <span style="color: #808080; font-family: 'Menlo';">能够改变页面中的所有<span style="color: #808080;"> HTML <span style="color: #808080; font-family: 'Menlo';">属性<span style="color: #808080;"><br><span style="color: #808080;"> - JavaScript <span style="color: #808080; font-family: 'Menlo';">能够改变页面中的所有<span style="color: #808080;"> CSS <span style="color: #808080; font-family: 'Menlo';">样式<span style="color: #808080;"><br><span style="color: #808080;"> - JavaScript <span style="color: #808080; font-family: 'Menlo';">能够对页面中的所有事件做出反应<br></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
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<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"> - 即<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;">Javascript<span style="color: #808080; font-family: 'Menlo';">可以操作四个内容<span style="color: #808080;">:，<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;">html<span style="color: #808080; font-family: 'Menlo';">元素、<span style="color: #808080;">html<span style="color: #808080; font-family: 'Menlo';">属性、<span style="color: #808080;">css<span style="color: #808080; font-family: 'Menlo';">样式、事件。<br> - HTML DOM 是浏览器对象BOM的一个属性</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
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3.DOM node level
<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">DOM定义了树节点（node）的层次和其Node接口:<br> - Document 最顶层的节点，所有的其它节点都是附属于它的。<br> - DocumentType DTD引用(使用<!DOCTYPE>)，如<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">。它不能包含子节点。<br> - DocumentFragment 可以像Document一样来保存其它节点。<br> - Element 表示起始标签和结束标签之间的内容。这是唯一可以同时包含特性和子节点的节点类型。<br> - Attr 代表一对特姓名和特性值。这个节点类型不能包含子节点。<br> - Text 代表XML文档中的在其实标签和结束标签之间的，或者CData Seciron内的普通文本。这个节点类型不能包含子节点。<br> - CDataSection <![CDATA[]]>的对象表现形式。这个几点类型仅能包含文本节点Text作为子节点。<br> - Entity 表示在DTD中的一个实体定义，例如<!ENTITY foo "foo">。这个节点类型不能包含子节点。<br> - EntityReference 代表一个实体引用，例如"。这个节点类型不能包含子节点。<br> - ProcessingInstruction 代表一个PI。这个节点类型不能包含子节点。<br> - Comment 代表XML注释。这个节点类型不能包含子节点。<br> - Notation 代表在DTD中定义的记号。这个很少用到。</span></span></span></span></span></span></span></span></span></span></span>
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4.Node type constants
<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">Node接口还定义了不同节点类型的12个常量:<br> - Document - Node.DOCUMENT_NODE<br> - DocumentType - Node.DOCUMENT_TYOE_NODE<br> - DoucmentR=Frament - Node.DOCUMENT_FRAMENT_NODE<br> - Element - Node.ELEMENT_NODE<br> - Attr - Node.ATTRIBUTE_NODE<br> - Text - Node.TEXT_NODE<br> - CDataSection - Node.CDATA_SECTION_NODE<br> - <span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">Entity </span></span></span></span></span></span></span></span></span></span></span>- Node.ENTITY_NODE<br> - EntityReference - Node.ENTITY_REFERENCE_NODE<br> - <span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">ProcessingInstruction </span></span></span></span></span></span></span></span></span></span></span>- Node.PROCESSING_INSTRUCTION_NODE<br> - Comment - Node.COMMENT_NODE<br> - Notation - Node.NOTATION_NODE<br>* 这些常量会在选择节点之后以属性的方式查询</span></span></span></span></span></span></span></span></span></span></span>
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4.Node type constants
<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">Node接口还定义了不同节点类型的12个常量:<br> - Document - Node.DOCUMENT_NODE(9)<br> - DocumentType - Node.DOCUMENT_TYOE_NODE(10)<br> - DoucmentR=Frament - Node.DOCUMENT_FRAMENT_NODE(11)<br> - Element - Node.ELEMENT_NODE(1)<br> - Attr - Node.ATTRIBUTE_NODE(2)<br> - Text - Node.TEXT_NODE(3)<br> - CDataSection - Node.CDATA_SECTION_NODE(4)<br> - <span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">Entity - Node.ENTITY_NODE(5)<br> - EntityReference - Node.ENTITY_REFERENCE_NODE(6)<br> - <span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">ProcessingInstruction - Node.PROCESSING_INSTRUCTION_NODE(7)<br> - Comment - Node.COMMENT_NODE(8)<br> - Notation - Node.NOTATION_NODE(12)<br>* 这些常量会在选择节点之后以属性的方式查询</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
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5.Node characteristics and methods
<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">Node接口定义了所有节点类型都包含的特性和方法:<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><br></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>
Copy after login
| Characteristics/Methods | Type/Return Type | Description |
| nodeName | String | node Name |
| nodeValue | String | ## The value of the node |
| nodeType | Number | The type constant value of the node |
| ownerDocument | Document | The document to which the node belongs |
| childNodes |
NodeList | List of all child nodes of the node |
| firstChild | Node | The first node in the child node list |
| lastChild | Node | The last child node list Node |
| hasChildNodes() | Boolean | Whether it contains children Node |
| appendChild(node) | Node | Append node Add to the end of childNodes |
| Node | Delete node from childNodes | |
| Node | Replace oldnode in childNodes with newnode | ## insertBefore(newnode, refnode) |
| Node | Insert newnode before refnode in childNodes | previousSibling |
| Node | points to the previous sibling node. If this node is the first sibling node, then the value is null | nextSibling |
| Node | points to the next sibling node. If this node is the last sibling node, then the value is null | attributes |
| NamedNodeMap | Contains the attributes that represent an element Attr object, only used for Element nodes |
6.HTML DOM<span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';">任何基于XML的语言，如XHTML和SVG，因为它们遵循XML语法，所以可以使用上述的Node接口操作。然而很多语言会继续定义它们自己的DOM来扩展XML以提供特定功能。<br>开发XML DOM的同时，W3C还一起开发了针对XHTML(以及HTML)的DOM。这个DOM定义了一个HTMLDocument一个HTMLElement作为实现基础。每个HTML元素通过它自己的HTMLElement类型表示，如HTMLpElement代表了<p>元素。但有少数的除外。</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span> Copy after login 二、DOM通用节点对象操作1.DOM的通用属性<span style="color: #808080;">alinkColor 激活的链接的颜色，如<body alink="color">定义的<br>bgColor 页面的背景颜色，如<body bgcolor="color">定义的<br>fgColor 页面的文本颜色，如<body text="color">定义的<br>lastModified 最后修改页面的日期，是字符串<br>linkColor 链接的颜色，如<body link="color">定义的<br>referrer 浏览器当前页后退一个位置的url<br>title <title>标签中显示的文本<br>URL 当前页面的url<br>vlinkColor 访问过的链接的颜色，如<body vlink="color">定义的<br>* 这些属性是引用了<body>标签中的旧HTML特性，应该用样式表代替它们。</span> Copy after login 2.DOM的通用集合<span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">ahchors 页面中所有锚的集合(由<a name="ahchorname></a>标签表示)<br>applets 页面中所有applet的集合<br>embeds 页面中所有嵌入式对象的集合(由<embed>标签表示)<br>forms 页面中所有表单的集合<br>images 页面中所有图像的集合<br>links 页面中所有链接的集合(由<a href="somewhere.htm"><a>表示</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span> Copy after login 3.DOM通用节点操作document对象是BOM的一部分，同时也是HTML DOM的HTMLDocument对象的表现形式，即它也是XML DOM Document对象。 Copy after login 1查找节点<span style="color: #808080;">document.getElementById() <span style="color: #808080; font-family: 'Menlo';"> 返回对拥有指定<span style="color: #808080;"> id <span style="color: #808080; font-family: 'Menlo';">的第一个对象的引用。<br><span style="color: #808080;">document.getElementsByName() <span style="color: #808080; font-family: 'Menlo';">返回带有指定名称的对象集合。<br><span style="color: #808080;">document.getElementsByTagName() <span style="color: #808080; font-family: 'Menlo';">返回带有指定标签名的对象集合。<br><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;">document.getElementsByClassName() <span style="color: #808080; font-family: 'Menlo';">返回带有指定类名的对象集合。</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span> Copy after login <!DOCTYPE html><html lang="en"><head>
<meta charset="UTF-8">
<title>document操作元素</title></head><body>
<p class="outer">
<p class="inner">第一段文本</p>
<p class="inner">第二段文本</p>
</p>
<script>
var op = document.getElementsByClassName("outer")[0].getElementsByClassName("inner")[0].innerHTML;
</script></body></html>Copy after login 2创建节点<span style="color: #808080;">document.createAttribute(name) 创建属性名为name的属性节点。<br/>document.createElement() 创建标签名为tagName的元素。<span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><br/><span style="color: #808080;">document.createTextNode(text) 创建包含文本text的文本节点。<span style="color: #808080; font-family: 'Menlo';"><br/><span style="color: #808080;">* 创建其它Node接口定义的节点没有太大用处。因为被更简便的操作替代。</span></span></span></span></span></span></span> Copy after login 3添加节点<span style="color: #808080;">Element.appendChild(Node) 添加Node子元素。<br/>Element.insertBefore(newNode, oldNode) <span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">在某个子节点对象前添加新节点。</span></span></span></span></span></span></span></span> Copy after login 4删除节点<span style="color: #808080;">Element.removeChild(Node) 删除Node子元素。</span> Copy after login 5替换节点<span style="color: #808080;">Element.replacChild(newNode, oldNode) 替换子元素。</span> Copy after login <span style="color: #808080;">document.getElementById() <span style="color: #808080; font-family: 'Menlo';"> 返回对拥有指定<span style="color: #808080;"> id <span style="color: #808080; font-family: 'Menlo';">的第一个对象的引用。<br/><span style="color: #808080;">document.getElementsByName() <span style="color: #808080; font-family: 'Menlo';">返回带有指定名称的对象集合。<br/><span style="color: #808080;">document.getElementsByTagName() <span style="color: #808080; font-family: 'Menlo';">返回带有指定标签名的对象集合。<br/><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;">document.getElementsByClassName() <span style="color: #808080; font-family: 'Menlo';">返回带有指定类名的对象集合。</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span> Copy after login 6.节点属性和方法<span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';">节点属性和方法包含DOM NOde接口定义的所有属性和方法。HTML DOM 还包括其它的一些属性和方法。详细参见http://www.w3school.com.cn/jsref/dom_obj_all.asp。</span></span></span></span></span></span></span></span> Copy after login <span style="color: #808080;">Element.tagName <span style="color: #808080; font-family: 'Menlo';">返回元素的标签名。 </span><br/>Element.cloneNode() 复制当前元素。<br/>Element.normalize() <span style="color: #808080; font-family: 'Menlo';">合并元素中相邻的文本节点，并移除空的文本节点。<br/></span>Element.parentNode <span style="color: #808080; font-family: 'Menlo';">返回元素的父节点。<br/></span>Element.ownerDocument <span style="color: #808080; font-family: 'Menlo';">返回元素的根元素（文档对象）。</span><span style="color: #808080; font-family: 'Menlo';"><br/></span>nodelist.item() <span style="color: #808080; font-family: 'Menlo';">返回<span style="color: #808080;"> NodeList <span style="color: #808080; font-family: 'Menlo';">中位于指定下标的节点。<br/><span style="color: #808080;">nodelist.length <span style="color: #808080; font-family: 'Menlo';">返回<span style="color: #808080;"> NodeList <span style="color: #808080; font-family: 'Menlo';">中的节点数。</span></span></span></span></span></span></span><span style="color: #808080; font-family: 'Menlo';"><br/></span>Element.toString() <span style="color: #808080; font-family: 'Menlo';">把元素转换为字符串。</span></span> Copy after login 4.DOM通用属性操作1.查找属性<span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;">Element.attributes<span style="color: #808080; font-family: 'Menlo';"> </span></span></span></span></span></span></span>返回元素属性的<span style="color: #808080; font-family: 'Fira Code';"> NamedNodeMap<span style="color: #808080;">。</span></span><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><br/></span></span></span></span>El</span></span></span></span></span></span>ement.hasAttribute() <span style="color: #808080; font-family: 'Menlo';">如果元素拥有指定属性，则返回<span style="color: #808080;">true<span style="color: #808080; font-family: 'Menlo';">，否则返回<span style="color: #808080;"> false<span style="color: #808080; font-family: 'Menlo';">。<br/><span style="color: #808080;">Element.hasAttributes() <span style="color: #808080; font-family: 'Menlo';">如果元素拥有属性，则返回<span style="color: #808080;"> true<span style="color: #808080; font-family: 'Menlo';">，否则返回<span style="color: #808080;"> fals</span></span></span></span></span></span></span></span></span></span></span> Copy after login 2.获取属性<span style="color: #808080;">Element.<span style="color: #808080;">getAttribute</span>() 返回元素节点的指定属性值。<br/>Element.<span style="color: #808080;">getAttributeNode</span>() <span style="color: #808080;">返回指定的属性节点</span>。</span> Copy after login 3.设置属性<span style="color: #808080;"><span style="color: #808080;">Element.setAttribute() <span style="color: #808080; font-family: 'Menlo';">把指定属性设置或更改为指定值。<br/><span style="color: #808080;">Element.setAttributeNode() <span style="color: #808080; font-family: 'Menlo';">设置或更改指定属性节点。</span></span></span></span></span> Copy after login 4.删除属性<span style="color: #808080;"><span style="color: #808080;">Element.removeAttribute() <span style="color: #808080; font-family: 'Menlo';">从元素中移除指定属性。<br/><span style="color: #808080;">Element.removeAttributeNode() <span style="color: #808080; font-family: 'Menlo';">移除指定的属性节点，并返回被移除的节点。</span></span></span></span></span> Copy after login 5.getattr和setattr获取或设置属性除了hasAttribute、getAttributes、setAttributes、removeAttribute操作属性，一些属性也可以通过节点.属性的方式获取/设置属性。 Copy after login <span style="color: #808080;">Element.id <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的<span style="color: #808080;"> id<span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><br/></span></span></span></span></span></span></span>Element.style <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的<span style="color: #808080;"> style <span style="color: #808080; font-family: 'Menlo';">属性。<br/><span style="color: #808080;">Element.innerHTML <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的内容。</span></span><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"> <br/></span></span></span></span></span></span></span>Element.className <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的<span style="color: #808080;"> class <span style="color: #808080; font-family: 'Menlo';">属性。<br/></span></span></span>Element.title <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的<span style="color: #808080;"> title <span style="color: #808080; font-family: 'Menlo';">属性。<br/><span style="color: #808080;">Element.textContent <span style="color: #808080; font-family: 'Menlo';">设置或返回节点及其后代的文本内容。</span></span> <br/><span style="color: #808080;">Element.contentEditable <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的文本方向。<br/></span></span></span></span></span>Element.dir <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的内容是否可编辑。</span></span> <br/><span style="color: #808080;">Element.accessKey <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的快捷键。<br/></span>Element.lang <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的语言代码。</span><span style="color: #808080; font-family: 'Menlo';"><br/></span>Element.namespaceURI <span style="color: #808080; font-family: 'Menlo';">返回元素的<span style="color: #808080;"> namespace URI<span style="color: #808080; font-family: 'Menlo';">。<br/></span></span></span>Element.tabIndex <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的<span style="color: #808080;"> tab <span style="color: #808080; font-family: 'Menlo';">键控制次序。</span></span></span></span> Copy after login <span style="color: #808080;">Element.clientHeight <span style="color: #808080; font-family: 'Menlo';">返回元素的可见高度。<br/><span style="color: #808080;">Element.clientWidth <span style="color: #808080; font-family: 'Menlo';">返回元素的可见宽度。<span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><span style="color: #808080;"><span style="color: #808080; font-family: 'Menlo';"><br/><span style="color: #808080;">Element.offsetWidth <span style="color: #808080; font-family: 'Menlo';"> 返回元素的宽度。<br/><span style="color: #808080;">Element.offsetLeft <span style="color: #808080; font-family: 'Menlo';"> 返回元素的水平偏移位置。<br/><span style="color: #808080;">Element.offsetParent <span style="color: #808080; font-family: 'Menlo';">返回元素的偏移容器。<br/><span style="color: #808080;">Element.offsetTop <span style="color: #808080; font-family: 'Menlo';">返回元素的垂直偏移位置。<br/></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>Element.scrollHeight <span style="color: #808080; font-family: 'Menlo';">返回元素的整体高度。<br/><span style="color: #808080;">Element.scrollLeft <span style="color: #808080; font-family: 'Menlo';">返回元素左边缘与视图之间的距离。<br/><span style="color: #808080;">Element.scrollTop <span style="color: #808080; font-family: 'Menlo';">返回元素上边缘与视图之间的距离。<br/><span style="color: #808080;">Element.scrollWidth <span style="color: #808080; font-family: 'Menlo';">返回元素的整体宽度。</span></span></span></span></span></span></span></span> Copy after login 6.检查元素<span style="color: #808080;">Element.isContentEditable <span style="color: #808080; font-family: 'Menlo';">设置或返回元素的内容。<br/><span style="color: #808080;">Element.isDefaultNamespace() <span style="color: #808080; font-family: 'Menlo';">如果指定的<span style="color: #808080;"> namespaceURI <span style="color: #808080; font-family: 'Menlo';">是默认的，则返回<span style="color: #808080;"> true<span style="color: #808080; font-family: 'Menlo';">，否则返回<span style="color: #808080;"> false<span style="color: #808080; font-family: 'Menlo';">。<br/><span style="color: #808080;">Element.isEqualNode() <span style="color: #808080; font-family: 'Menlo';">检查两个元素是否相等。<br/><span style="color: #808080;">Element.isSameNode() <span style="color: #808080; font-family: 'Menlo';">检查两个元素是否是相同的节点。<br/><span style="color: #808080;">Element.compareDocumentPosition() <span style="color: #808080; font-family: 'Menlo';">比较两个元素的文档位置。<br/><span style="color: #808080;">Element.isSupported() <span style="color: #808080; font-family: 'Menlo';">如果元素支持指定特性，则返回<span style="color: #808080;"> true<span style="color: #808080; font-family: 'Menlo';">。</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span> Copy after login 以上就是本文的全部内容，希望对大家的学习有所帮助，更多相关内容请关注PHP中文网！ 相关推荐： |
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There is no absolute salary for Python and JavaScript developers, depending on skills and industry needs. 1. Python may be paid more in data science and machine learning. 2. JavaScript has great demand in front-end and full-stack development, and its salary is also considerable. 3. Influencing factors include experience, geographical location, company size and specific skills.
How to merge array elements with the same ID into one object using JavaScript?
Apr 04, 2025 pm 05:09 PM
How to merge array elements with the same ID into one object in JavaScript? When processing data, we often encounter the need to have the same ID...
Is JavaScript hard to learn?
Apr 03, 2025 am 12:20 AM
Learning JavaScript is not difficult, but it is challenging. 1) Understand basic concepts such as variables, data types, functions, etc. 2) Master asynchronous programming and implement it through event loops. 3) Use DOM operations and Promise to handle asynchronous requests. 4) Avoid common mistakes and use debugging techniques. 5) Optimize performance and follow best practices.
How to achieve parallax scrolling and element animation effects, like Shiseido's official website?
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How can we achieve the animation effect accompanied by page scrolling like Shiseido's official website?
Apr 04, 2025 pm 05:36 PM
Discussion on the realization of parallax scrolling and element animation effects in this article will explore how to achieve similar to Shiseido official website (https://www.shiseido.co.jp/sb/wonderland/)...
The difference in console.log output result: Why are the two calls different?
Apr 04, 2025 pm 05:12 PM
In-depth discussion of the root causes of the difference in console.log output. This article will analyze the differences in the output results of console.log function in a piece of code and explain the reasons behind it. �...
How to implement panel drag and drop adjustment function similar to VSCode in front-end development?
Apr 04, 2025 pm 02:06 PM
Explore the implementation of panel drag and drop adjustment function similar to VSCode in the front-end. In front-end development, how to implement VSCode similar to VSCode...
