Namespace Xpath
Class CValueCompareExtension

class CValueCompareExtension: public CInterface {
public:
    CValueCompareExtension();
    virtual ~CValueCompareExtension();
public:
    virtual bool NodeSetToValue(
        const XContext &pContext,
        int nOp,
        const XValue &pValue1,
        const XValue &pValue2) = 0;
    virtual bool ValueToNodeSet(
        const XContext &pContext,
        int nOp,
        const XValue &pValue1,
        const XValue &pValue2) = 0;
    };

The abstract interface to value comparison handlers for extension XPath value types.

The library or application that supports extension XPath types must supply a class derived from CValueCompareExtension that implements comparison of extension XPath value types with XPath node-set values. Implementation of a class derived from CValueCompareExtension is usually provided as part of the CXpathImplementation class implementation.

Since:

1.00.00

Version:

1.00.00

Author:

Alexey Gokhberg

See Also:

CValue, CContext, CValueCompare, CXpathImplementation

CValueCompareExtension

CValueCompareExtension();

Constructs the extension value comparison handler.

~CValueCompareExtension

virtual ~CValueCompareExtension();

Destroys the extension value comparison handler.

NodeSetToValue

virtual bool NodeSetToValue(
    const XContext &pContext,
    int nOp,
    const XValue &pValue1,
    const XValue &pValue2) = 0;

Compares the XPath node-set value to the value of the extension type.

The code of the comparison operation must be supplied as a parameter to this function. Operation codes are defined in the anonymous enumeration of CValueCompare class declaration.

Parameters:

pContext - the XPath context that controls comparison

nOp - the code of the comparison operation

pValue1 - the node-set value to compare

pValue2 - the extension value to compare

Returns:

true if the result of comparison is true; false otherwise

ValueToNodeSet

virtual bool ValueToNodeSet(
    const XContext &pContext,
    int nOp,
    const XValue &pValue1,
    const XValue &pValue2) = 0;

Compares the value of the extension type to the XPath node-set value.

The code of the comparison operation must be supplied as a parameter to this function. Operation codes are defined in the anonymous enumeration of CValueCompare class declaration.

Parameters:

pContext - the XPath context that controls of comparison

nOp - the code of the comparison operation

pValue1 - the extension value to compare

pValue2 - the node-set value to compare