2.1 KiB
XPathEvaluator
The xpath.parse() method returns an XPathEvaluator, which contains the following methods.
Each of these methods takes an optional options object, which can contain any of the following properties:
namespaces - a namespace resolver. See the [documentation page](namespace resolvers.md) for details.
variables - a variable resolver. See the [documentation page](variable resolvers.md) for details.
functions - a function resolver. See the [documentation page](function resolvers.md) for details.
node - the context node for evaluating the expression
Example usage:
var evaluator = xpath.parse('/characters/character[@greeting = $greeting]');
var character = evaluator.select1({
node: myCharacterDoc,
variables: {
greeting: 'Hello, I'm Harry, Harry Potter.`
}
});
XPathEvaluator methods
evaluate([options])
Evaluates the XPath expression and returns the result. The resulting type is determined based on the type of the expression, using the same criteria as [xpath.select](xpath methods.md).
evaluateNumber([options])
Evaluates the XPath expression and returns the result as a number.
evaluateString([options])
Evaluates the XPath expression and returns the result as a string.
evaluateBoolean([options])
Evaluates the XPath expression and returns the result as a boolean value.
evaluateNodeSet([options])
Evaluates the XPath expression and returns the result as an XNodeSet. See the documentation page for details on this interface.
This is only valid for expressions that evaluate to a node set.
select([options])
Evaluates the XPath expression and returns an array of the resulting nodes, in document order.
This is only valid for expressions that evaluate to a node set.
select([options])
Evaluates the XPath expression and returns an array of the resulting nodes, in document order.
This is only valid for expressions that evaluate to a node set.
select1([options])
Evaluates the XPath expression and the first node in the resulting node set, in document order. Returns undefined
This is only valid for expressions that evaluate to a node set.