XPathEvaluator: createExpression() method
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
This method compiles an XPathExpression which can then be used for
(repeated) evaluations of the XPath expression.
Syntax
createExpression(expression)
createExpression(expression, resolver)
Parameters
expression-
A string representing the XPath expression to be created.
resolverOptional-
A
Node,null, or any object implementing thelookupNamespaceURImethod. Permits translation of all prefixes, including thexmlnamespace prefix, within the XPath expression into appropriate namespace URIs.
Return value
A XPathExpression representing the compiled form of the XPath
expression.
Exceptions
INVALID_EXPRESSION_ERR
If the expression is not legal according to the rules of the
XPathEvaluator, a DOMException of type
INVALID_EXPRESSION_ERR is raised.
NAMESPACE_ERR
If the expression contains namespace prefixes which cannot be resolved by the specified
XPathNSResolver, a DOMException of type
NAMESPACE_ERROR is raised.
Examples
The following example shows the use of the evaluate() method.
HTML
<div>XPath example</div>
<div>Number of <div>s: <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
Specifications
| Specification |
|---|
| DOM # dom-xpathevaluatorbase-createexpression |
Browser compatibility
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