This method compiles an XPathExpression
which can then be used for (repeated) evaluations of the XPath expression.
XPathEvaluator.createExpression()
Syntax
createExpression(expression) createExpression(expression, resolver)
Parameters
- expression
-
A string representing the XPath expression to be created.
- resolver Optional
-
Permits translation of all prefixes, including the
xml
namespace 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
, an XPathException
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.
Example
The following example shows the use of the evaluate()
method.
HTML
<div>XPath example</div> <div>Number of <div>s: <output></output></div>
JavaScript
var xpath = "//div"; var evaluator = new XPathEvaluator(); var expression = evaluator.createExpression(xpath); var result = expression.evaluate(document, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE); document.querySelector("output").textContent = result.snapshotLength;
Result
Specifications
Specification |
---|
DOM Standard # dom-xpathevaluatorbase-createexpression |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
createExpression |
1
|
12
|
1
|
No
|
≤12.1
|
3
|
1
|
18
|
4
|
≤12.1
|
1
|
1.0
|
See also
© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/XPathEvaluator/createExpression