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web api interface

XPathEvaluator

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The XPathEvaluator interface allows to compile and evaluate XPath expressions.

Constructor

Instance methods

  • createExpression()
    • : Creates a parsed XPath expression with resolved namespaces.
  • createNSResolver() Deprecated
    • : Returns the input as-is.
  • evaluate()
    • : Evaluates an XPath expression string and returns a result of the specified type if possible.

Example

Count the number of <div> elements

The following example shows the use of the XPathEvaluator interface.

HTML

<div>XPath example</div>
<div>Number of &lt;div&gt; elements: <output></output></div>

JavaScript

const xpath = "//div";
const evaluator = new XPathEvaluator();
const expression = evaluator.createExpression(xpath);
const result = expression.evaluate(
  document,
  XPathResult.ORDERED_NODE_SNAPSHOT_TYPE,
);
document.querySelector("output").textContent = result.snapshotLength;

Result

Interactive exampleOpen the canonical MDN source to run this embedded demo.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also