1.9 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. See the links for each item for further details:
-
namespaces- a namespace resolver -
variables- a variable resolver -
functions- a function resolver -
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.
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.
select1([options])
Evaluates the XPath expression and the first node in the resulting node set, in document order. Returns undefined if the resulting node set is empty.
This is only valid for expressions that evaluate to a node set.