IXPathEvaluatorEvaluate Method |
Evaluates an XPath expression string and returns a result of the specified type if possible.
Namespace: Aspose.Html.Dom.XPathAssembly: Aspose.HTML (in Aspose.HTML.dll) Version: 20.3
SyntaxIXPathResult Evaluate(
string expression,
Node contextNode,
IXPathNSResolver resolver,
XPathResultType type,
Object result
)
Function Evaluate (
expression As String,
contextNode As Node,
resolver As IXPathNSResolver,
type As XPathResultType,
result As Object
) As IXPathResult
IXPathResult^ Evaluate(
String^ expression,
Node^ contextNode,
IXPathNSResolver^ resolver,
XPathResultType type,
Object^ result
)
abstract Evaluate :
expression : string *
contextNode : Node *
resolver : IXPathNSResolver *
type : XPathResultType *
result : Object -> IXPathResult
Parameters
- expression
- Type: SystemString
The XPath expression string to be parsed and evaluated. - contextNode
- Type: Aspose.Html.DomNode
The context is context node for the evaluation of this
XPath expression. If the IXPathEvaluator was obtained by casting the
Document then this must be owned by the same document and must be a
Document, Element, Attr, Text,
CDATASection, Comment, ProcessingInstruction,
or XPathNamespace node. If the context node is a Text or a
CDATASection, then the context is interpreted as the whole logical text node
as seen by XPath, unless the node is empty in which case it may not serve as the XPath context. - resolver
- Type: Aspose.Html.Dom.XPathIXPathNSResolver
The resolver permits translation of all prefixes, including
the xml namespace prefix, within the XPath expression into appropriate namespace URIs.
If this is specified as null, any namespace prefix within the expression will result
in DOMException being thrown with the code NAMESPACE_ERR. - type
- Type: Aspose.Html.Dom.XPathXPathResultType
If a specific type is specified, then the result will be returned as
the corresponding type. For XPath 1.0 results, this must be one of the values of the
XPathResultType enum. - result
- Type: SystemObject
The result specifies a specific result object which may be reused
and returned by this method. If this is specified as null or the implementation does not
reuse the specified result, a new result object will be constructed and returned. For XPath 1.0
results, this object will be of type IXPathResult.
Return Value
Type:
IXPathResultThe result of the evaluation of the XPath expression. For XPath 1.0 results, this object
will be of type
IXPathResult.
ExceptionsException | Condition |
---|
DOMException | INVALID_EXPRESSION_ERR: Raised if the expression is not legal according
to the rules of the IXPathEvaluator. |
DOMException | TYPE_ERR: Raised if the result cannot be converted to return the
specified type. |
DOMException | NAMESPACE_ERR: Raised if the expression contains namespace prefixes
which cannot be resolved by the specified IXPathNSResolver. |
DOMException | WRONG_DOCUMENT_ERR: The Node is from a document that is not supported
by this IXPathEvaluator. |
DOMException | NOT_SUPPORTED_ERR: The Node is not a type permitted as an XPath context
node or the request type is not permitted by this IXPathEvaluator. |
See Also