XML XPath Wildcard
- XPath wildcard can be used to match an element or attribute without needing to specify the exact name in the XPath expression.
- The wildcard character is an asterisk (*).
Syntax
The following is the syntax of the XPath wildcard:
XPathExpression/*
XPathExpression/@*
Example
Consider the following XML document:
<bookstore>
<book>
<title>Harry Potter and the Philosopher's Stone</title>
<author>J. K. Rowling</author>
</book>
<book>
<title>Lord of the Rings</title>
<author>J. R. R. Tolkien</author>
</book>
</bookstore>
The following are examples of wildcards in XPath expressions:
//bookstore/*
This would match all child elements, in this case, all the book
elements and all their child elements.
//bookstore/book/*
This would match all child elements of the book
elements, in this case, the title
and author
elements.
//bookstore/*/author
This would match all author
elements that are children of any element directly under bookstore
, in this case, the author
elements of both the book
elements.
//bookstore/book[1]/*
This would match all child elements of the first book
element, in this case, the title
and author
elements of the first book
.
Output
The output of an XPath expression with a wildcard will be all of the elements or attributes that match the pattern.
Explanation
The XPath wildcard allows for matching all elements or attributes that fit a certain pattern without needing to specify the exact name in the expression. This can be useful when searching for specific types of elements or attributes within an XML document.
Use
The XPath wildcard can be used to match elements or attributes that follow a pattern, such as matching all elements of a certain type or all attributes with a certain name prefix. This can help simplify XPath expressions and make them more flexible.
Important Points
- The XPath wildcard is denoted by an asterisk (*).
- The wildcard can be used in element and attribute expressions.
- The wildcard matches any element or attribute that fits the pattern, regardless of the name.
- Wildcards can be combined with other XPath expressions to create more complex queries.
Summary
XPath wildcard is a powerful tool for matching elements or attributes that follow a certain pattern without needing to specify the exact name in the expression. This can help simplify XPath expressions and make them more flexible.