Abstract base class for a string based Value type. More...

#include <value.hpp>

Inheritance diagram for Exiv2::StringValueBase:

[legend]

Public Types
typedef std::auto_ptr< StringValueBase >	AutoPtr
	Shortcut for a StringValueBase auto pointer.

Public Types inherited from Exiv2::Value
typedef std::auto_ptr< Value >	AutoPtr
	Shortcut for a Value auto pointer.

Public Member Functions
Creators
	StringValueBase (TypeId typeId)
	Constructor for subclasses.

	StringValueBase (TypeId typeId, const std::string &buf)
	Constructor for subclasses.

	StringValueBase (const StringValueBase &rhs)
	Copy constructor.

virtual	~StringValueBase ()
	Virtual destructor.

Manipulators
virtual int	read (const std::string &buf)
	Read the value from buf. This default implementation uses buf as it is.

virtual int	read (const byte *buf, long len, ByteOrder byteOrder=invalidByteOrder)
	Read the value from a character buffer. More...

Public Member Functions inherited from Exiv2::Value
	Value (TypeId typeId)
	Constructor, taking a type id to initialize the base class with.

virtual	~Value ()
	Virtual destructor.

virtual int	setDataArea (const byte *buf, long len)
	Set the data area, if the value has one by copying (cloning) the buffer pointed to by buf. More...

TypeId	typeId () const
	Return the type identifier (Exif data format type).

AutoPtr	clone () const
	Return an auto-pointer to a copy of itself (deep copy). The caller owns this copy and the auto-pointer ensures that it will be deleted.

std::string	toString () const
	Return the value as a string. Implemented in terms of write(std::ostream& os) const of the concrete class.

virtual std::string	toString (long n) const
	Return the n-th component of the value as a string. The default implementation returns toString(). The behaviour of this method may be undefined if there is no n-th component.

virtual long	sizeDataArea () const
	Return the size of the data area, 0 if there is none.

virtual DataBuf	dataArea () const
	Return a copy of the data area if the value has one. The caller owns this copy and DataBuf ensures that it will be deleted. More...

bool	ok () const
	Check the ok status indicator. After a to<Type> conversion, this indicator shows whether the conversion was successful.

Accessors
std::string	value_
	Stores the string value.

AutoPtr	clone () const

virtual long	copy (byte *buf, ByteOrder byteOrder=invalidByteOrder) const
	Write value to a character data buffer. More...

virtual long	count () const
	Return the number of components of the value.

virtual long	size () const
	Return the size of the value in bytes.

virtual long	toLong (long n=0) const
	Convert the n-th component of the value to a long. The behaviour of this method may be undefined if there is no n-th component. More...

virtual float	toFloat (long n=0) const
	Convert the n-th component of the value to a float. The behaviour of this method may be undefined if there is no n-th component. More...

virtual Rational	toRational (long n=0) const
	Convert the n-th component of the value to a Rational. The behaviour of this method may be undefined if there is no n-th component. More...

virtual std::ostream &	write (std::ostream &os) const
	Write the value to an output stream. You do not usually have to use this function; it is used for the implementation of the output operator for Value, operator<<(std::ostream &os, const Value &value).

StringValueBase &	operator= (const StringValueBase &rhs)
	Assignment operator.

virtual StringValueBase *	clone_ () const =0
	Internal virtual copy constructor.

Additional Inherited Members
Static Public Member Functions inherited from Exiv2::Value
static AutoPtr	create (TypeId typeId)
	A (simple) factory to create a Value type. More...

Protected Member Functions inherited from Exiv2::Value
Value &	operator= (const Value &rhs)
	Assignment operator. Protected so that it can only be used by subclasses but not directly.

Protected Attributes inherited from Exiv2::Value
bool	ok_
	Indicates the status of the previous to<Type> conversion.

Detailed Description

Abstract base class for a string based Value type.

Uses a std::string to store the value and implements defaults for most operations.

Member Function Documentation

◆ copy()

virtual long Exiv2::StringValueBase::copy	(	byte *	buf,
		ByteOrder	byteOrder = `invalidByteOrder`
	)		const

virtual

Write value to a character data buffer.

The user must ensure that the buffer has enough memory. Otherwise the call results in undefined behaviour.

Note: The byte order is required by the interface but not used by this method, so just use the default.

Parameters

buf	Data buffer to write to.
byteOrder	Byte order. Not used.

Returns: Number of characters written.

Implements Exiv2::Value.

Reimplemented in Exiv2::CommentValue.

◆ read()

virtual int Exiv2::StringValueBase::read	(	const byte *	buf,
		long	len,
		ByteOrder	byteOrder = `invalidByteOrder`
	)

virtual

Read the value from a character buffer.

Note: The byte order is required by the interface but not used by this method, so just use the default.

Parameters

buf	Pointer to the data buffer to read from
len	Number of bytes in the data buffer
byteOrder	Byte order. Not needed.

Returns: 0 if successful.

Implements Exiv2::Value.

Reimplemented in Exiv2::CommentValue.

◆ toFloat()

virtual float Exiv2::StringValueBase::toFloat ( long n = 0 ) const

virtual

Convert the n-th component of the value to a float. The behaviour of this method may be undefined if there is no n-th component.

Returns: The converted value.

Implements Exiv2::Value.

◆ toLong()

virtual long Exiv2::StringValueBase::toLong ( long n = 0 ) const

virtual

Convert the n-th component of the value to a long. The behaviour of this method may be undefined if there is no n-th component.

Returns: The converted value.

Implements Exiv2::Value.

◆ toRational()

virtual Rational Exiv2::StringValueBase::toRational ( long n = 0 ) const

virtual

Convert the n-th component of the value to a Rational. The behaviour of this method may be undefined if there is no n-th component.

Returns: The converted value.

Implements Exiv2::Value.

The documentation for this class was generated from the following file:

value.hpp

Public Types

Public Member Functions

Accessors

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ copy()

◆ read()

◆ toFloat()

◆ toLong()

◆ toRational()