Hướng dẫn python xml xpath query
What is XPath?XPath is a major element in the XSLT standard. Show XPath can be used to navigate through elements and attributes in an XML document.
XPath Path ExpressionsXPath uses path expressions to select nodes or node-sets in an XML document. These path expressions look very much like the path expressions you use with traditional computer file systems: XPath Standard FunctionsXPath includes over 200 built-in functions. There are functions for string values, numeric values, booleans, date and time comparison, node manipulation, sequence manipulation, and much more. Today XPath expressions can also be used in JavaScript, Java, XML Schema, PHP, Python, C and C++, and lots of other languages. XPath is Used in XSLTXPath is a major element in the XSLT standard. With XPath knowledge you will be able to take great advantage of your XSLT knowledge. XPath is a W3C RecommendationXPath 1.0 became a W3C Recommendation on November 16, 1999. XPath 2.0 became a W3C Recommendation on January 23, 2007. XPath 3.0 became a W3C Recommendation on April 8, 2014. XPath uses path expressions to select nodes or node-sets in an XML document. The node is selected by following a path or steps. The XML Example DocumentWe will use the following XML document in the examples below.
Selecting NodesXPath uses path expressions to select nodes in an XML document. The node is selected by following a path or steps. The most useful path expressions are listed below:
In the table below we have listed some path expressions and the result of the expressions:
PredicatesPredicates are used to find a specific node or a node that contains a specific value. Predicates are always embedded in square brackets. In the table below we have listed some path expressions with predicates and the result of the expressions:
Selecting Unknown NodesXPath wildcards can be used to select unknown XML nodes.
In the table below we have listed some path expressions and the result of the expressions:
Selecting Several PathsBy using the | operator in an XPath expression you can select several paths. In the table below we have listed some path expressions and the result of the expressions:
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