TVarData represents Variant information.
TVarData = packed record case Integer of 0: (VType: TVarType; Reserved1: Word; Reserved2: Word; Reserved3: Word;); 1: (VLongs: array[0..2] of LongInt); RawData: array [0..3] of LongInt);); 2: (VWords: array [0..6] of Word); VBytes: array [0..13] of Byte);); varAny: (VAny: Pointer;); varArray: (VArray: PVarArray;); varBoolean: (VBoolean: WordBool;); varByRef: (VPointer: Pointer;); varByte: (VByte: Byte;); varCurrency: (VCurrency: Currency;); varDate: (VDate: TDateTime;); varDispatch: (VDispatch: Pointer;); varDouble: (VDouble: Double;); varError: (VError: HRESULT;); varInt64: (VInt64: Int64;); varInteger: (VInteger: Integer;); varLongWord: (VLongWord: LongWord;); varOleStr: (VOleStr: PWideChar;); varShortInt: (VShortInt: ShortInt;); varSingle: (VSingle: Single;); varSmallInt: (VSmallInt: SmallInt;); varString: (VString: Pointer;); varUnknown: (VUnknown: Pointer;); varWord: (VWord: Word;); end;
struct TVarData { TVarType VType; Word Reserved1; Word Reserved2; Word Reserved3; SmallInt VSmallInt; int VInteger; Single VSingle; Double VDouble; Currency VCurrency; TDateTime VDate; PWideChar VOleStr; void * VDispatch; HRESULT VError; WordBool VBoolean; void * VUnknown; ShortInt VShortInt; Byte VByte; Word VWord; LongWord VLongWord; Int64 VInt64; void * VString; void * VAny; PVarArray VArray; void * VPointer; array[0..2] of LongInt) VLongs; array [0..6] of Word) VWords; array [0..13] of Byte) VBytes; array [0..3] of LongInt) RawData; };
System
TVarData is the base class for Variant.
{ union { Word VType; // Delphi-compatible - Variant Type member VARTYPE vt; // tagVARIANT compatible member }; Word Reserved1; Word Reserved2; Word Reserved3; union { // Delphi-compatible Variant members Smallint VSmallint; // iVal Integer VInteger; // lVal Single VSingle; // fltVal Double VDouble; // dblVal CurrencyBase VCurrency; // cyVal TDateTimeBase VDate; // date PWideChar VOleStr; // bstrVal IDispatch* VDispatch; // pdispVal HResult VError; // scode WordBool VBoolean; // boolVal IUnknown* VUnknown; // punkVal Byte VByte; // bVal Pointer VString; // ?????? PVarArray VArray; // parray Pointer VPointer; // byref // tagVARIANT compatible members (from OAIDL.H) // Allowing all types marked as [V] (may appear in a VARIANT to be initialized LONG lVal; BYTE bVal; SHORT iVal; FLOAT fltVal; DOUBLE dblVal; VARIANT_BOOL boolVal; SCODE scode; CY cyVal; DATE date; BSTR bstrVal; IUnknown *punkVal; IDispatch *pdispVal; SAFEARRAY *parray; BYTE *pbVal;SHORT *piVal; LONG *plVal; FLOAT *pfltVal; DOUBLE *pdblVal; VARIANT_BOOL *pboolVal; SCODE *pscode; CY *pcyVal; DATE *pdate; BSTR *pbstrVal; IUnknown **ppunkVal; IDispatch **ppdispVal; SAFEARRAY **pparray; VARIANT *pvarVal; PVOID byref; CHAR cVal; USHORT uiVal; ULONG ulVal; INT intVal; UINT uintVal; DECIMAL *pdecVal; CHAR *pcVal; USHORT *puiVal; ULONG *pulVal; INT *pintVal; UINT *puintVal; }; };
The VType of TVarData contains the type code of the variant in the lower twelve bits (the bits defined by varTypeMask).
The following values are used for VType:
#define varEmpty (Byte)(0)
#define varNull (ByteByte_Type)(1) #define varSmallint (ByteByte_Type)(2) #define varInteger (ByteByte_Type)(3) #define varSingle (ByteByte_Type)(4) #define varDouble (ByteByte_Type)(5) #define varCurrency (ByteByte_Type)(6) #define varDate (ByteByte_Type)(7) #define varOleStr (ByteByte_Type)(8) #define varDispatch (ByteByte_Type)(9) #define varError (ByteByte_Type)(10) #define varBoolean (ByteByte_Type)(11) #define varVariant (ByteByte_Type)(12) #define varUnknown (ByteByte_Type)(13) #define varByte (ByteByte_Type)(17) #define varString (WordWord_Type)(256) #define varTypeMask (WordWord_Type)(4095) #define varArray (WordWord_Type)(8192) #define varByRef (WordWord_Type)(16384) #define varStrArg (ByteByte_Type)(72) #define vtInteger (ByteByte_Type)(0) #define vtBoolean (ByteByte_Type)(1) #define vtChar (ByteByte_Type)(2) #define vtExtended (ByteByte_Type)(3) #define vtString (ByteByte_Type)(4) #define vtPointer (ByteByte_Type)(5) #define vtPChar (ByteByte_Type)(6) #define vtObject (ByteByte_Type)(7) #define vtClass (ByteByte_Type)(8) #define vtWideChar (ByteByte_Type)(9) #define vtPWideChar (ByteByte_Type)(10) #define vtAnsiString (ByteByte_Type)(11) #define vtCurrency (ByteByte_Type)(12) #define vtVariant (ByteByte_Type)(13)
In addition, the varArray bit may be set to indicate that the variant is an array, and the varByRef bit may be set to indicate that the variant contains a reference as opposed to a value.
Word Reserved1;
File Word Reserved2;
Word Reserved3;The Reserved1, Reserved2, and Reserved3 members of TVarData are unused.
union { Smallint VSmallint;
Integer VInteger;
Single VSingle;
Double VDouble;
CurrencyBase VCurrency;
TDateTimeBase VDate;
PWideChar VOleStr;
Ole2::IDispatch* VDispatch;
Integer VError;
WordBool VBoolean;
Ole2::IUnknown* VUnknown;
Byte VByte;
Pointer VString;
PVarArray VArray;
Pointer VPointer;
};
};The contents of the remaining eight bytes of TVarData depend on the VType field. If neither the varArray nor the varByRef bits are set, the variant contains a value of the given type.
If the varArray bit is set, the variant contains a pointer to a TVarArray structure that defines the specifics of the array. The type of each array element is given by the varTypeMask bits in VType.
If the varByRef bit is set, the variant contains a reference to a value of the type given by the varTypeMask and varArray bits in VType.
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