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XMLParserItf Interface CATIXMLXPathExpression

Usage: an implementation of this interface is supplied and you must use it as is. You should not reimplement it.

interface CATIXMLXPathExpression

Interface to represent an XPath expression.
Role: An XPath expression represents a path in a DOM tree from a root node (called the context node) to a set of target nodes (called the result set nodes). XPath expressions can be used to retrieve nodes from a DOM tree and make DOM programs more compact.

See also:

Method Index

o EvaluateAsNode(CATIDOMNode_var&): Evaluates an XPath expression of type "node list" and returns the first item in its result set.
o EvaluateAsNodeList(CATIDOMNodeList_var&): Evaluates an XPath expression of type "node list" and returns its result set.
o GetContext(CATIDOMNode_var&): Returns the context node for this expression.
o GetExpression(CATUnicodeString&): Returns the XPath expression represented by this object.
o GetNamespacePrefixes(CATListOfCATUnicodeString&,CATListOfCATUnicodeString&): Returns the binding of prefixes used in this XPath expression.
o SetNamespacePrefixes(CATListOfCATUnicodeString&,CATListOfCATUnicodeString&): Specifies the binding of prefixes used in this XPath expression.

Methods

o EvaluateAsNode

public virtual EvaluateAsNode( oResult)

Evaluates an XPath expression of type "node list" and returns the first item in its result set. The expression must evaluate to a node list (as opposed to a boolean, a string or a number), or an error will be returned. If the expression evaluates to an empty list, NULL_var is returned.

Parameters:

oResult: The first node of the result set, or NULL_var if no node matches the expression.

Returns:

If the method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

o EvaluateAsNodeList

public virtual EvaluateAsNodeList( oResult)

Evaluates an XPath expression of type "node list" and returns its result set. The expression must evaluate to a node list (as opposed to a boolean, a string or a number), or an error will be returned. The expression may evaluate to an empty node list.

Parameters:

oResult: The result set obtained by evaluating this expression.

Returns:

If the method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

o GetContext

public virtual GetContext( oContext)

Returns the context node for this expression. The context node is the DOM node (either a CATIDOMElement_var or a CATIDOMDocument_var instance) where the expression evaluation will begin.

Parameters:

oContext: The context node for this expression.

Returns:

If the method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

o GetExpression

public virtual GetExpression( oExpression)

Returns the XPath expression represented by this object.

Parameters:

oExpression: The XPath expression represented by this object.

Returns:

If the method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

o GetNamespacePrefixes

public virtual GetNamespacePrefixes(		`oPrefixes`,
		`oNamespaceURIs`)

Returns the binding of prefixes used in this XPath expression. You must define one such binding for each prefix your XPath expression uses before invoking EvaluateAsNodeList or EvaluateAsNode.

Returns:: If the method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

o SetNamespacePrefixes

public virtual SetNamespacePrefixes(	const	`iPrefixes`,
	const	`iNamespaceURIs`)

Specifies the binding of prefixes used in this XPath expression. You must define one such binding for each prefix your XPath expression uses before invoking EvaluateAsNodeList or EvaluateAsNode.

Returns:: If the method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

This object is included in the file: CATIXMLXPathExpression.h
If needed, your Imakefile.mk should include the module: CatXmlItfExt