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How to select XML nodes based on an attribute value with XPath?
How to select XML nodes based on an attribute value with XPath?
To select XML nodes by attribute value in XPath, use predicates with @attribute='value'. For exact matches, /books/book[@category='fiction'] selects books with category fiction. Use //product[@id='123'] to find a product by ID. For partial matches, apply contains(), like //item[@type='hardcover' and contains(@title, 'Lord')]. When handling multi-value attributes like tags, //item[contains(@tags, 'sci-fi')] works if values are space-separated. To check attribute existence, use //input[@disabled]. Combine conditions with and or or, such as //user[@active='true' and @role='admin']. Exclude nodes using not(), like //node[not(@hidden)] or //node[@status!='archived']. This approach enables precise, flexible node selection based on attribute criteria.
To select XML nodes based on an attribute value using XPath, you use a predicate in square brackets that specifies the attribute condition. The basic syntax targets elements by checking their attributes with @attribute='value'.
Select Nodes by Exact Attribute Value
Use the equality operator to match a specific attribute value.
● To select all book elements where the category attribute is "fiction": /books/book[@category='fiction']● To find a product with id equal to "123": //product[@id='123']
Match Partial or Multiple Values
Sometimes attribute values contain multiple terms (e.g., space-separated) or you need partial matches.
● Use contains() for partial matches: //item[@type='hardcover' and contains(@title, 'Lord')]● For attributes with multiple values (like
class="sci-fi novel"), use contains() carefully or tokenization if supported. In standard XPath 1.0:
//item[contains(@tags, 'sci-fi')]
Use Other Conditions and Functions
You can combine conditions using boolean logic or check existence.
● Select nodes where an attribute exists, regardless of value: //input[@disabled]● Combine conditions with and, or: //user[@active='true' and @role='admin']
● Use not() to exclude values: //node[@status!='archived'] or //node[not(@hidden)] Basically, filtering XML nodes by attribute value in XPath relies on predicates with @ syntax. It's flexible enough for exact matches, existence checks, and conditional logic.
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