XPathEvaluator - Web APIs 编辑

The XPathEvaluator interface allows to compile and evaluate XPath expressions.

It is implemented by the Document interface.

Methods

XPathEvaluator.createExpression()

Creates a parsed XPath expression with resolved namespaces.

XPathEvaluator.createNSResolver()

Adapts any DOM node to resolve namespaces allowing the XPath expression to be evaluated relative to the context of the node where it appeared within the document.

XPathEvaluator.evaluate()

Evaluates an XPath expression string and returns a result of the specified type if possible.

Example

The following example shows the use of the XPathEvaluator interface.

HTML

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

JavaScript

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

Result

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• document.createExpression()
• XPathExpression