#ifndef _NORCOM_VARIANT_
#define _NORCOM_VARIANT_
// This class was written in order to standardize what VT_ value types
// (e.g., VT_I4, VT_BSTR, VT_R4) are valid for each possible 'C' data
// type (e.g., long, short, string).
// Note: Because ALL of the GetXXXX member functions are VERY similar it
// would seem like the right thing to do would be to implement A SINGLE
// 'GetValue(...)' function and have multiple versions with different
// input parameters, right? This works BUT requires lots of casting
// as all the various flavors pass their parameters by reference. We
// decided that we would simply leave it as different function names...
#define WI_INVALIDVARIANTTYPE 1 // Invalid Variant Type.
#define WI_INVALIDEMPTYVARIANT 2 // Invalid EMPTY variant
class CVariantHandler
{
public:
// MUST use non-default constructor
//
// (or default constructor in conjunction with Setvariant(...) )
_declspec (dllexport) CVariantHandler();
_declspec (dllexport) CVariantHandler(const VARIANT FAR& Variant);
_declspec (dllexport) ~CVariantHandler();
///////////////////////////////////////////////////////////////////////////////
//
// SetVariant(const VARIANT FAR& Variant)
//
// Sets the Variant. (Either after calling the default constructor, or
// when reusing a previously constructed instance)
//
// INPUT PARAMETERS:
//
// VARIANT FAR& - reference to Variant data member to be accessed.
//
// OUTPUT:
//
// none
//
///////////////////////////////////////////////////////////////////////////////
_declspec (dllexport) void SetVariant(const VARIANT FAR& Variant);
///////////////////////////////////////////////////////////////////////////////
//
// long CVariantHandler::GetLong( long &Value,
// const long &Default,
// const BOOL EmptyIsError)
//
// Gets the long value of a Variant data item.
//
// Currently allows values of type:
// VT_I4
// VT_I2
//
// INPUT PARAMETERS:
//
// long &Value - reference to long value to be returned
//
// long &Default - reference to the Default value to be returned if
// the EmptyIsError parameter is set to FALSE and the
// Variant is VT_EMPTY.
//
// BOOL EmptyIsError - TRUE will cause a VT_EMPTY Variant to return a
// WI_INVALIDVARIANTTYPE error.
//
// Note that this is the default such that a call
// of type GetLong(X) can simply be coded to allow
// no default case.
//
// FALSE will cause a VT_Empty Variant to return
// the specified Default.
//
// Note that as EmptyIsDefault is the last parameter
// in order to specify a value of FALSE a value for
// the Default parameter MUST be specified.
//
// OUTPUT:
//
// 0 - success.
// WI_INVALIDVARIANTTYPE - Invalid Variant Type.
// WI_INVALIDEMPTYVARIANT - Invalid EMPTY variant
//
///////////////////////////////////////////////////////////////////////////////
_declspec (dllexport) long GetLong(long &Value, const long &Default, const BOOL EmptyIsError = TRUE);
///////////////////////////////////////////////////////////////////////////////
//
// long CVariantHandler::GetShort( short &Value,
// const short &Default,
// const BOOL EmptyIsError)
//
// Gets the short value of a Variant data item.
//
// Currently allows values of type:
// VT_I2
//
// INPUT PARAMETERS:
//
// short &Value - reference to short value to be returned
//
// short &Default - reference to the Default value to be returned if
// the EmptyIsError parameter is set to FALSE and the
// Variant is VT_EMPTY.
//
// BOOL EmptyIsError - TRUE will cause a VT_EMPTY Variant to return a
// WI_INVALIDVARIANTTYPE error.
//
// Note that this is the default such that a call
// of type GetLong(X) can simply be coded to allow
// no default case.
//
// FALSE will cause a VT_Empty Variant to return
// the specified Default.
//
// Note that as EmptyIsDefault is the last parameter
// in order to specify a value of FALSE a value for
// the Default parameter MUST be specified.
//
// OUTPUT:
//
// 0 - success.
// WI_INVALIDVARIANTTYPE - Invalid Variant Type.
// WI_INVALIDEMPTYVARIANT - Invalid EMPTY variant
//
///////////////////////////////////////////////////////////////////////////////
_declspec (dllexport) long GetShort(short &Value, const short &Default, const BOOL EmptyIsError = TRUE);
///////////////////////////////////////////////////////////////////////////////
//
// long CVariantHandler::GetCString( CString &Value,
// const CString &Default,
// const BOOL EmptyIsError)
//
// Gets the CString value of a Variant data item.
//
// Currently allows values of type:
// VT_BSTR
//
// INPUT PARAMETERS:
//
// CString &Value - reference to CString value to be returned
//
// CString &Default - The Default value to be returned if the
// EmptyIsError parameter is set to FALSE and the
// Variant is VT_EMPTY.
//
// BOOL EmptyIsError - TRUE will cause a VT_EMPTY Variant to return a
// WI_INVALIDVARIANTTYPE error.
//
// Note that this is the default such that a call
// of type GetLong(X) can simply be coded to allow
// no default case.
//
// FALSE will cause a VT_Empty Variant to return
// the specified Default.
//
// Note that as EmptyIsDefault is the last parameter
// in order to specify a value of FALSE a value for
// the Default parameter MUST be specified.
//
// OUTPUT:
//
// 0 - success.
// WI_INVALIDVARIANTTYPE - Invalid Variant Type.
// WI_INVALIDEMPTYVARIANT - Invalid EMPTY variant
//
///////////////////////////////////////////////////////////////////////////////
_declspec (dllexport) long GetCString(CString &Value, const CString &Default, const BOOL EmptyIsError = TRUE);
///////////////////////////////////////////////////////////////////////////////
//
// long CVariantHandler::GetBool( BOOL &Value,
// const BOOL &Default,
// const BOOL EmptyIsError)
//
// Gets the boolean value of a Variant data item.
//
// Currently allows values of type:
// VT_BOOL
//
// INPUT PARAMETERS:
//
// BOOL &Value - reference to boolean value to be returned
//
// BOOL &Default - reference to the Default value to be returned if
// the EmptyIsError parameter is set to FALSE and the
// Variant is VT_EMPTY.
//
// BOOL EmptyIsError - TRUE will cause a VT_EMPTY Variant to return a
// WI_INVALIDVARIANTTYPE error.
//
// Note that this is the default such that a call
// of type GetLong(X) can simply be coded to allow
// no default case.
//
// FALSE will cause a VT_Empty Variant to return
// the specified Default.
//
// Note that as EmptyIsDefault is the last parameter
// in order to specify a value of FALSE a value for
// the Default parameter MUST be specified.
//
// OUTPUT:
//
// 0 - success.
// WI_INVALIDVARIANTTYPE - Invalid Variant Type.
// WI_INVALIDEMPTYVARIANT - Invalid EMPTY variant
//
///////////////////////////////////////////////////////////////////////////////
_declspec (dllexport) long GetBool(BOOL &Value, const BOOL &Default, const BOOL EmptyIsError = TRUE);
///////////////////////////////////////////////////////////////////////////////
//
// long CVariantHandler::GetFloat( float &Value,
// const float &Default,
// const BOOL EmptyIsError)
//
// Gets the float (4 byte real) value of a Variant data item.
//
// Currently allows values of type:
// VT_R4
//
// INPUT PARAMETERS:
//
// float &Value - reference to boolean value to be returned
//
// float &Default - reference to the Default value to be returned if
// the EmptyIsError parameter is set to FALSE and the
// Variant is VT_EMPTY.
//
// BOOL EmptyIsError - TRUE will cause a VT_EMPTY Variant to return a
// WI_INVALIDVARIANTTYPE error.
//
// Note that this is the default such that a call
// of type GetLong(X) can simply be coded to allow
// no default case.
//
// FALSE will cause a VT_Empty Variant to return
// the specified Default.
//
// Note that as EmptyIsDefault is the last parameter
// in order to specify a value of FALSE a value for
// the Default parameter MUST be specified.
//
// OUTPUT:
//
// 0 - success.
// WI_INVALIDVARIANTTYPE - Invalid Variant Type.
// WI_INVALIDEMPTYVARIANT - Invalid EMPTY variant
//
///////////////////////////////////////////////////////////////////////////////
_declspec (dllexport) long GetFloat(float &Value, const float &Default, const BOOL EmptyIsError = TRUE);
///////////////////////////////////////////////////////////////////////////////
//
// long CVariantHandler::GetDouble( double &Value,
// const double &Default,
// const BOOL EmptyIsError)
//
// Gets the double (8 byte real) value of a Variant data item.
//
// Currently allows values of type:
// VT_R8
//
// INPUT PARAMETERS:
//
// double &Value - reference to boolean value to be returned
//
// double &Default - reference to the Default value to be returned if
// the EmptyIsError parameter is set to FALSE and the
// Variant is VT_EMPTY.
//
// BOOL EmptyIsError - TRUE will cause a VT_EMPTY Variant to return a
// WI_INVALIDVARIANTTYPE error.
//
// Note that this is the default such that a call
// of type GetLong(X) can simply be coded to allow
// no default case.
//
// FALSE will cause a VT_Empty Variant to return
// the specified Default.
//
// Note that as EmptyIsDefault is the last parameter
// in order to specify a value of FALSE a value for
// the Default parameter MUST be specified.
//
// OUTPUT:
//
// 0 - success.
// WI_INVALIDVARIANTTYPE - Invalid Variant Type.
// WI_INVALIDEMPTYVARIANT - Invalid EMPTY variant
//
///////////////////////////////////////////////////////////////////////////////
_declspec (dllexport) long GetDouble(double &Value, const double &Default, const BOOL EmptyIsError = TRUE);
private:
// Holder of Variant to be operated upon...
VARIANT m_Variant;
// Used to ensure that a Variant has been set
// prior to calling a Getxxx function...
BOOL m_Initialized;
};
#endif //ifndef