XLink is an attribute-based syntax for defining links in XML documents. An XLink can connect from a point A to a point B be (similar to the known from HTML hyperlink element ). However, you can also send documents in two directions connect ( ie from A to B and back as well ). Furthermore, XLink also represent compounds multidirectional (different distances between any number of XML documents ). The documents on which an XLink shows must be no XML documents.
XLink is a recommendation of the World Wide Web Consortium. Despite hesitant implementation of the W3C XLink can still perceive as the future standard for hyperlinks on the WWW, giving it explicitly preferred over other methods such as particular Hlink.
XLinks be incorporated into XML elements with arbitrary element names by the elements specific XML attributes of the XML namespace are added http://www.w3.org/1999/xlink (usually the prefix xlink bound ).
Simple XLinks can be located in any element and can be described by the following attributes:
- You will xlink by the attribute assignment: type = " simple" explained.
- The actual reference contains the attribute xlink: href = " reference ", where reference is to be replaced by a Uniform Resource Identifier, which by definition also may include an XPointer expression for intra-document references.
Optional attributes are:
- Xlink: title that contains a user-friendly title of the reference. All types of XLink elements may attributed a xlink: title attribute support, the below mentioned extended types.
- Xlink: show, which specifies how the reference to appear, and the new values , replace, embed, other, none can assume
- Xlink: actuate, which determines when the reference is to be pursued, and that can take the values onLoad, onRequest, other, accept none
- Xlink: role, which describes the importance of links with each other. It contains a URI, the comments on the remote resource or explained.
- Xlink: arcrole, is identical to the semantics of xlink: role, however, describes arc elements that no xlink: role attribute can take. It includes an absolute URI that points to a description of the resource. The resource indicates the relation which describes the arc.
Advanced XLinks provide opportunities for bi- directional and multi -references and references to references. Unlike the simple XLinks several elements are necessary for this purpose:
- An element with the xlink: type = " extended" virtually forms the framework of the extended XLinks. It may not, without a xlink: title the above-mentioned Xlink: Wear role.
The functionality of the complex so declared XLinks is defined in sub-elements that can be named anything back and be with the following attributes to XLink elements:
- With xlink: type = " locator " xlink elements have attributed as another attribute: href = contain " URI ", where URI is replaced by a Uniform Resource Identifier. Logically, there is also an attribute xlink: label and thus a name of the declared URI represents.
- Xlink: type = "resource" adds a resource that can be referenced within the document. In order for these resources can be addressed at all by other links, the specification of an xlink is: label attribute necessary.
It has up to this point no actual references, but document internal and external URIs, which are each represented by a label. These are used now with ( a ) another sub-element (s ) of the element with xlink: type = " extended" relate to each other:
- A with xlink: type = " arc" Nonattributed element contains usefully following attributes: xlink: from = " ..." and xlink: to = " ... " where the previously defined labels are used. Optionally, the previously discussed attributes xlink: title, xlink: show, xlink: actuate, xlink: arcrole
Below is an overview of the support for the W3C XLink recommendation by various applications.
Mozilla Firefox has limited support for simple XLinks. (As of September 20, 2009 )
- Links with an xlink: show = "embed " attribute does not work.
Internet Explorer, Opera, Google Chrome
No support. (As of September 20, 2009 )