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Evaluates an XPath expression using the scanner for the class instance with the specified context node and XPath environment.
Source position: laz2_xpath.pas line 460
public function TXPathExpression.Evaluate( |
AContextNode: TDOMNode |
):TXPathVariable; |
AContextNode: TDOMNode; |
AEnvironment: TXPathEnvironment |
AContextNode |
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Context node for the expression. |
Value from the evaluated expression.
AContextNode |
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Context node for the expression. |
AEnvironment |
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XPath environment for the evaluation. |
Evaluate is an overloaded method in TXPathExpression used to select node(s) or value(s) in the specified context which match an XPath expression. It returns a TXPathVariable type which contains the node(s) or value(s) which match the expression used in the XPath scanner for the class instance.
An overloaded variant allows the XPath environment to be provided during expression evaluation. The TXPathEnvironment argument allows variable names, variable values, and functions to be added to or removed from the execution environment. It also provides an implementation of the core functions in the XPath function library.
Evaluate iteratively calls the Evaluate method for nodes in the root context to capture the return value for the method.
No actions are performed in the method if a root node has not been assigned in the XPath scanner. In this situation, the return value is Nil.
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Provides access to functions and variables available in the XPath environment. |
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Implements a lexical scanner and parser using XPath syntax and semantics. |
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Base class used to represent an XPath variables and results. |
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Specifies the method used to evaluate an XPath Predicate Expression. |
| Version 4.0 | Generated 2025-05-03 | Home |