What is XSL and what is it used for?

XSL stands for Extensible Stylesheet Language, which is used to understand and style XML documents. It can be used as an XML-based stylesheet language, just like CSS is an HTML-based stylesheet language; It is a markup language that specifies how a browser should render an XML document.

# Simply put, XSL is a language used to present XML data in a readable format. The data in XML can be formatted in a user-specified format. to output the display. We can make XML data displayed in different formats by writing XSL styles for XML.

Main parts of XSL:

XSLT: It is a language that transforms XML documents into various other types of documents.

XPath: It is a language for navigating in XML documents.

XQuery: It is a language for querying XML documents.

XSL FO: It is a language for formatting XML documents.

Note: XSLT stands for XSL Transformation, which is used to convert XML documents into other formats (such as converting XML to HTML); it is the most important part of XSL.

XSL document composition description:

1. Declaration definition in the header of the XSL document

The first line of XML declaration:

Because XSL is a standard XML format, and all XML documents begin with an XML declaration, the same is true for XSL style sheets. The first line of any XSL document is actually They are also XML declarations:

<?xml version="1.0" encoding="ISO-8859-1"?>

The second line of XSL declaration:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">....</xsl:stylesheet>

If we need to access the elements, attributes and characteristics in XSLT, we must declare the XSLT namespace at the top of the document. That is,

version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"

Note: The content part of the XSL document must be written in strict accordance with xml rules, that is, there must be start and end tags.

2. The content part of the XSL document

The content part of the XSL document must be included in the xsl:template tag:

<xsl:template match="/">......</xsl:template>

Description: xsl:template tag is used to carry data in XML documents.

How to reference XSL files in XML?

Just like external CSS style files can be referenced in HTML, we can also reference XSL files in XML. The basic syntax is as follows:

<?xml-stylesheet type="text/xsl" href="你的xsl文件路径"?>

Summary : The above is the entire content of this article, I hope it will be helpful to everyone's study.

The above is the detailed content of What is XSL and what is it used for?. For more information, please follow other related articles on the PHP Chinese website!