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Full-stack JavaScript (24) DOM2 and DOM3, which do not involve XML namespace extension, dom2dom3
(1) three attributes are added to the DocumentType change: publicId, systemId, and internalSubset (internal subset)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"[<!ELEMENT name (#PCDATA)>] >
Export document.doc type. internalSubset will get "<! ELEMENT name (# PCDATA)> ". This internal subset (internal subset) is rarely used in HTML and may be more common in XML.
(2) importNode () method, which is unrelated to xml naming, is used to retrieve a node from a Document and put it in another Document to become a part of the Document.
Note that each node has an ownerDocument. If the appendChild (node) method is used, an error is returned if the input node is not in the same document.
The importNode () method is similar to the cloneNode () method. It accepts two parameters: one is the time to import, and the other is a Boolean value, indicating whether to import subnodes.
Var newNode = document. importNode (oldNode, true) // import all child nodes document. body. appendChild (newnode)
var parentWindow = document.defaultView || document.parentWindow
In addition to the importNode () method and the defaultView attribute, two methods are added:
Document. implementation. createDocumentType (document type name, publicId, systemId). Because the existing document type cannot be modified, you can only call this method when creating a new document.
Document. implementation. createDocument (namaspaceURL, root, doctype );
Example:
var doctype = document.implementation.createDocumentType("html","-//W3C//DTD XHTML 1.0 Strict//EN","http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd")
var doc = document.implementation.createDocument("http://www.w3.org/1999/xhtml","html", doctype);
(3) a namespace-independent method is added for Node type changes. The isSupported () method is similar to the document. hasFeature () method in dom1 to determine the capabilities of the current Node.
However, we recommend that you use capability testing.
Example:
if(document.body.isSupported('html','2.0')) { //...}
Both methods accept a node parameter and return true if the input node is the same or equal to the referenced node.
The so-called "same" means that two nodes reference the same object.
Equality means that two nodes are of the same type and have the same attributes (nodeName, nodeValue, and so on ), and their attributes and childNodes attributes are also equal (the same position contains the same value ).
DOM3 also introduces a new method setUserData () for adding additional data to the Node. This method will specify the data to the Node and accept three parameters: Key, value, and processing function.
document.body.setUserData("name","100",function(opration,key,value,srcNode,destNode){})
SetUserData (), callback function, with 5 parameters,
The processing function (callback function) in setUserData () is called when a node with data is copied, deleted, renamed, or introduced into a document, therefore, you can determine in advance how to process user data when the preceding operations occur.
(4) framework changes
Although the framework and the internal framework are represented by HTMLFrameElement and HTMLIframeElement, they both have a new attribute in dom2: contentDocument
Var iframe = document. getElementById ("myIframe"); var iframeDoc = iframe. contentDocument; // IE8 is invalid
IE8 does not support the contentDocment attribute of the framework, but supports the contentWindow attribute.
Therefore:
var iframe = document.getElementById("myIframe");var iframeDoc = iframe.contentDocument || iframe.contentWindow.document;
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