Version: 3.1.1
wxMemoryInputStream Class Reference

#include <wx/mstream.h>

+ Inheritance diagram for wxMemoryInputStream:

Detailed Description

This class allows to use all methods taking a wxInputStream reference to read in-memory data.

Example:

// we've got a block of memory containing a BMP image and we want
// to use wxImage to load it:
wxMemoryInputStream stream(my_memory_block, size);
wxImage theBitmap;
if (!theBitmap.LoadFile(stream, wxBITMAP_TYPE_BMP))
return;
// we can now safely delete the original memory buffer as the data
// has been decoded by wxImage:
delete [] my_memory_block;

Library:  wxBase
Category:  Streams
See also
wxStreamBuffer, wxMemoryOutputStream

Public Member Functions

 wxMemoryInputStream (const void *data, size_t len)
 Initializes a new read-only memory stream which will use the specified buffer data of length len. More...
 
 wxMemoryInputStream (const wxMemoryOutputStream &stream)
 Creates a new read-only memory stream, initializing it with the data from the given output stream stream. More...
 
 wxMemoryInputStream (wxInputStream &stream, wxFileOffset len=wxInvalidOffset)
 Creates a new read-only memory stream, initializing it with the data from the given input stream stream. More...
 
virtual ~wxMemoryInputStream ()
 Destructor. More...
 
wxStreamBufferGetInputStreamBuffer () const
 Returns the pointer to the stream object used as an internal buffer for that stream. More...
 
- Public Member Functions inherited from wxInputStream
 wxInputStream ()
 Creates a dummy input stream. More...
 
virtual ~wxInputStream ()
 Destructor. More...
 
virtual bool CanRead () const
 Returns true if some data is available in the stream right now, so that calling Read() wouldn't block. More...
 
virtual bool Eof () const
 Returns true after an attempt has been made to read past the end of the stream. More...
 
int GetC ()
 Returns the first character in the input queue and removes it, blocking until it appears if necessary. More...
 
virtual size_t LastRead () const
 Returns the last number of bytes read. More...
 
virtual char Peek ()
 Returns the first character in the input queue without removing it. More...
 
virtual wxInputStreamRead (void *buffer, size_t size)
 Reads the specified amount of bytes and stores the data in buffer. More...
 
wxInputStreamRead (wxOutputStream &stream_out)
 Reads data from the input queue and stores it in the specified output stream. More...
 
bool ReadAll (void *buffer, size_t size)
 Reads exactly the specified number of bytes into the buffer. More...
 
virtual wxFileOffset SeekI (wxFileOffset pos, wxSeekMode mode=wxFromStart)
 Changes the stream current position. More...
 
virtual wxFileOffset TellI () const
 Returns the current stream position or wxInvalidOffset if it's not available (e.g. More...
 
size_t Ungetch (const void *buffer, size_t size)
 This function is only useful in read mode. More...
 
bool Ungetch (char c)
 This function acts like the previous one except that it takes only one character: it is sometimes shorter to use than the generic function. More...
 
- Public Member Functions inherited from wxStreamBase
 wxStreamBase ()
 Creates a dummy stream object. More...
 
virtual ~wxStreamBase ()
 Destructor. More...
 
wxStreamError GetLastError () const
 This function returns the last error. More...
 
virtual wxFileOffset GetLength () const
 Returns the length of the stream in bytes. More...
 
virtual size_t GetSize () const
 This function returns the size of the stream. More...
 
virtual bool IsOk () const
 Returns true if no error occurred on the stream. More...
 
virtual bool IsSeekable () const
 Returns true if the stream supports seeking to arbitrary offsets. More...
 
void Reset (wxStreamError error=wxSTREAM_NO_ERROR)
 Resets the stream state. More...
 
bool operator! () const
 Returns the opposite of IsOk(). More...
 

Additional Inherited Members

- Protected Member Functions inherited from wxInputStream
size_t OnSysRead (void *buffer, size_t bufsize)=0
 Internal function. More...
 
- Protected Member Functions inherited from wxStreamBase
virtual wxFileOffset OnSysSeek (wxFileOffset pos, wxSeekMode mode)
 Internal function. More...
 
virtual wxFileOffset OnSysTell () const
 Internal function. More...
 

Constructor & Destructor Documentation

wxMemoryInputStream::wxMemoryInputStream ( const void *  data,
size_t  len 
)

Initializes a new read-only memory stream which will use the specified buffer data of length len.

The stream does not take ownership of the buffer, i.e. the buffer will not be deleted in its destructor.

wxMemoryInputStream::wxMemoryInputStream ( const wxMemoryOutputStream stream)

Creates a new read-only memory stream, initializing it with the data from the given output stream stream.

wxMemoryInputStream::wxMemoryInputStream ( wxInputStream stream,
wxFileOffset  len = wxInvalidOffset 
)

Creates a new read-only memory stream, initializing it with the data from the given input stream stream.

The len argument specifies the amount of data to read from the stream. Setting it to wxInvalidOffset means that the stream is to be read entirely (i.e. till the EOF is reached).

virtual wxMemoryInputStream::~wxMemoryInputStream ( )
virtual

Destructor.

Does NOT free the buffer provided in the ctor.

Member Function Documentation

wxStreamBuffer* wxMemoryInputStream::GetInputStreamBuffer ( ) const

Returns the pointer to the stream object used as an internal buffer for that stream.