What's the difference between an element and a node in XML?

问题

I\'m working in Java with XML and I\'m wondering; what\'s the difference between an element and a node?

回答1:

The Node object is the primary data type for the entire DOM.

A node can be an element node, an attribute node, a text node, or any other of the node types explained in the "Node types" chapter.

An XML element is everything from (including) the element's start tag to (including) the element's end tag.

回答2:

Different W3C specifications define different sets of "Node" types.

Thus, the DOM spec defines the following types of nodes:

Document -- Element (maximum of one), ProcessingInstruction, Comment, DocumentType
DocumentFragment -- Element, ProcessingInstruction, Comment, Text, CDATASection, EntityReference
DocumentType -- no children
EntityReference -- Element, ProcessingInstruction, Comment, Text, CDATASection, EntityReference
Element -- Element, Text, Comment, ProcessingInstruction, CDATASection, EntityReference
Attr -- Text, EntityReference
ProcessingInstruction -- no children
Comment -- no children
Text -- no children
CDATASection -- no children
Entity -- Element, ProcessingInstruction, Comment, Text, CDATASection, EntityReference
Notation -- no children

The XML Infoset (used by XPath) has a smaller set of nodes:

The Document Information Item

Element Information Items

Attribute Information Items

Processing Instruction Information Items

Unexpanded Entity Reference Information Items

Character Information Items

Comment Information Items

The Document Type Declaration Information Item

Unparsed Entity Information Items

Notation Information Items

Namespace Information Items

XPath has the following Node types:

root nodes
element nodes
text nodes
attribute nodes
namespace nodes
processing instruction nodes
comment nodes

The answer to your question "What is the difference between an element and a node" is:

An element is a type of node. Many other types of nodes exist and serve different purposes.

回答3:

A Node is a part of the DOM tree, an Element is a particular type of Node

e.g. <foo> This is Text </foo>

You have a foo Element, (which is also a Node, as Element inherits from Node) and a Text Node 'This is Text', that is a child of the foo Element/Node

回答4:

A node can be a number of different kinds of things: some text, a comment, an element, an entity, etc. An element is a particular kind of node.

回答5:

As described in the various XML specifications, an element is that which consists of a start tag, and end tag, and the content in between, or alternately an empty element tag (which has no content or end tag). In other words, these are all elements:

<foo> stuff </foo>
<foo bar="baz"></foo>
<foo baz="qux" />

Though you hear "node" used with roughly the same meaning, it has no precise definition per XML specs. It's usually used to refer to nodes of things like DOMs, which may be closely related to XML or use XML for their representation.

回答6:

An xml document is made of nested elements. An element begins at its opening tag and ends at its closing tag. You're probably seen <body> and </body> in html. Everything between the opening and closing tags is the element's content. If an element is defined by a self-closing tag (eg. <br/>) then its content is empty.

Opening tags can also specify attributes, eg. <p class="rant">. In this example the attribute name is 'class' and its value 'rant'.

The XML language has no such thing as a 'node'. Read the spec, the word doesn't occur.

Some people use the word 'node' informally to mean element, which is confusing because some parsers also give the word a technical meaning (identifying 'text nodes' and 'element nodes'). The exact meaning depends on the parser, so the word is ill-defined unless you state what parser you are using. If you mean element, say 'element'.

回答7:

A node is the base class for both elements and attributes (and basically all other XML representations too).

回答8:

Element is the only kind of node that can have child nodes and attributes.

Document also has child nodes, BUT
no attributes, no text, exactly one child element.

回答9:

A node is defined as:

the smallest unit of a valid, complete structure in a document.

or as:

An object in the tree view that serves as a container to hold related objects.

Now their are many different kinds of nodes as an elements node, an attribute node etc.

回答10:

Now i know ,the element is one of node

All node types in here"http://www.w3schools.com/dom/dom_nodetype.asp"

Element is between the start tag and end in the end tag

So text node is a node , but not a element.

回答11:

An element is a type of node as are attributes, text etc.

回答12:

XML Element is a XML Node but with additional elements like attributes.

<a>Lorem Ipsum</a>  //This is a node

<a id="sample">Lorem Ipsum</a>  //This is an element

回答13:

node & element are same. Every element is a node , but it's not that every node must be an element.

来源：https://stackoverflow.com/questions/132564/whats-the-difference-between-an-element-and-a-node-in-xml

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xml

xmlnode

What&#39;s the difference between an element and a node in XML?

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