What is XPath

XPath, the XML path language, is a language for finding information in XML documents, determining the location of certain parts of the XML document, and traversing elements and attributes in the XML document.

XPath is an important core component of the XSLT standard and an important component of XSL; before learning XPath, you must first have a basic understanding of XML, XSL, and XSLT understanding. This article gives a brief introduction to XPath so that everyone can have a simple understanding of XPath. I hope it will be helpful to you. [Recommended video tutorials: XPath Tutorial]

Important functions of XPath

XPath is an XML-based tree Structural, which provides different types of expressions to retrieve relevant information from an XML document (nodes can be found in the data structure tree), is a syntax for defining parts of an XML document.

Let’s take a look at the important functions of XPath:

1. XPath defines the structure: XPath can be used to define various parts of the XML document, namely elements, attributes, text, namespaces, Process directives, comments and documentation nodes.

2. XPath provides path expressions: XPath provides powerful path expressions in XML documents, which are used to select nodes or node lists in XML documents.

3. XPath is the core component of XSLT: XPath is a major element in the XSLT standard and must be followed to use XSLT documents.

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XPath’s path expression

XPath defines a pattern or path expression that it uses to perform conversions. Path expressions look very similar to the general expressions we use in traditional file systems:

Seven types of nodes are specified in XPath, which can output and execute XPath expressions Formula:

Root, element, text, attribute, comment, processing instruction, namespace

Let’s take a look at the most useful expressions:

Based on the above expressions, let’s take a look at some path expression examples, with a description of the results:

Summary: The above is all of this article Content, I hope it will be helpful to everyone’s study.

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