wxScopedCharTypeBuffer< T > Class Template Reference

#include <wx/buffer.h>

Inheritance diagram for wxScopedCharTypeBuffer< T >:

Detailed Description

template<typename T>
class wxScopedCharTypeBuffer< T >

wxScopedCharTypeBuffer<T> is a template class for storing characters.

Data are stored in reference-counted buffer. In other words, making a copy of wxScopedCharTypeBuffer<T> will not make another copy of the stored string data, it will still point to the same location in memory.

wxScopedCharTypeBuffer<T> supports two storage modes: owned and non-owned. "Owned" data buffer (created with CreateOwned() or wxCharTypeBuffer<T> derived class) owns the data and frees them when the last buffer pointing to them is destroyed.

"Non-owned" buffer (created with CreateNonOwned()), on the other hand, references data owned by somebody else – typical use is by wxString::mb_str() or wxString::wc_str(), which may return non-owned buffer pointing to wxString's internal store.

Because of this, the validity of data stored in wxScopedCharTypeBuffer<T> is limited by the lifetime of the "parent" object that created the buffer (e.g. the wxString on which mb_str() was called).

If you need to preserve the data for longer, assign it to wxCharTypeBuffer<T> instead of wxScopedCharTypeBuffer<T>. On the other hand, use wxScopedCharTypeBuffer<T> if the buffer is to be destroyed before the "parent" object – typical use would be creating it on the stack and destroying when it goes out of scope (hence the class' name).

Template Parameters

T	The type of the characters stored in this class.

Since

2.9.0

Library:  None; this class implementation is entirely header-based.

Category:  Data Structures

Public Types
typedef T	CharType
	Stored characters type.

Public Member Functions
	wxScopedCharTypeBuffer ()
	Default constructor, creates NULL buffer.
	wxScopedCharTypeBuffer (const wxScopedCharTypeBuffer &src)
	Copy constructor.
wxScopedCharTypeBuffer &	operator= (const wxScopedCharTypeBuffer &src)
	Assignment operator behaves in the same way as the copy constructor.
	~wxScopedCharTypeBuffer ()
	Destructor.
void	reset ()
	Resets the buffer to NULL, freeing the data if necessary.
CharType *	data ()
	Returns pointer to the stored data.
const CharType *	data () const
	Returns const pointer to the stored data.
size_t	length () const
	Returns length of the string stored.
	operator const CharType * () const
	Implicit conversion to C string.
CharType	operator[] (size_t n) const
	Random access to the stored C string.

Static Public Member Functions
static const wxScopedCharTypeBuffer	CreateNonOwned (const CharType *str, size_t len=wxNO_LEN)
	Creates non-owned buffer from string data str.
static const wxScopedCharTypeBuffer	CreateOwned (CharType *str, size_t len=wxNO_LEN)
	Creates owned buffer from str and takes ownership of it.

Member Typedef Documentation

template<typename T>

typedef T wxScopedCharTypeBuffer< T >::CharType

Stored characters type.

Constructor & Destructor Documentation

template<typename T>

wxScopedCharTypeBuffer< T >::wxScopedCharTypeBuffer

(

)

Default constructor, creates NULL buffer.

template<typename T>

wxScopedCharTypeBuffer< T >::wxScopedCharTypeBuffer

(

const wxScopedCharTypeBuffer< T > &

src

)

Copy constructor.

Increases reference count on the data, does not make wxStrdup() copy of the data.

template<typename T>

wxScopedCharTypeBuffer< T >::~wxScopedCharTypeBuffer

(

)

Destructor.

Frees stored data if it is in "owned" mode and data's reference count reaches zero.

Member Function Documentation

template<typename T>

static const wxScopedCharTypeBuffer wxScopedCharTypeBuffer< T >::CreateNonOwned ( const CharType *  str, size_t  len = wxNO_LEN  )

static

Creates non-owned buffer from string data str.

The buffer's destructor will not destroy str. The returned buffer's data is valid only as long as str is valid.

Parameters

str	String data.
len	If specified, length of the string, otherwise the string is considered to be NUL-terminated.

template<typename T>

static const wxScopedCharTypeBuffer wxScopedCharTypeBuffer< T >::CreateOwned ( CharType *  str, size_t  len = wxNO_LEN  )

static

Creates owned buffer from str and takes ownership of it.

The buffer's destructor will free str when its reference count reaches zero (initial count is 1).

Parameters

str	String data.
len	If specified, length of the string, otherwise the string is considered to be NUL-terminated.

template<typename T>

CharType* wxScopedCharTypeBuffer< T >::data

(

)

Returns pointer to the stored data.

template<typename T>

const CharType* wxScopedCharTypeBuffer< T >::data

(

)

const

Returns const pointer to the stored data.

template<typename T>

size_t wxScopedCharTypeBuffer< T >::length

(

)

const

Returns length of the string stored.

template<typename T>

wxScopedCharTypeBuffer< T >::operator const CharType *

(

)

const

Implicit conversion to C string.

template<typename T>

wxScopedCharTypeBuffer& wxScopedCharTypeBuffer< T >::operator=

(

const wxScopedCharTypeBuffer< T > &

src

)

Assignment operator behaves in the same way as the copy constructor.

template<typename T>

CharType wxScopedCharTypeBuffer< T >::operator[]

(

size_t

n

)

const

Random access to the stored C string.

template<typename T>

void wxScopedCharTypeBuffer< T >::reset

(

)

Resets the buffer to NULL, freeing the data if necessary.