include/wx/sstream.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/sstream.h
   3 // Purpose:     string-based streams
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     2004-09-19
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2004 Vadim Zeitlin <vadim@wxwindows.org>
   9 // Licence:     wxWindows licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_SSTREAM_H_
  13 #define _WX_SSTREAM_H_
  14
  15 #include "wx/stream.h"
  16
  17 #if wxUSE_STREAMS
  18
  19 // ----------------------------------------------------------------------------
  20 // wxStringInputStream is a stream reading from the given (fixed size) string
  21 // ----------------------------------------------------------------------------
  22
  23 class WXDLLIMPEXP_BASE wxStringInputStream : public wxInputStream
  24 {
  25 public:
  26     // ctor associates the stream with the given string which makes a copy of
  27     // it
  28     wxStringInputStream(const wxString& s)
  29         : m_str(s)
  30     {
  31         m_pos = 0;
  32     }
  33
  34     virtual size_t GetSize() const { return m_str.length(); }
  35
  36 protected:
  37     virtual off_t OnSysSeek(off_t ofs, wxSeekMode mode);
  38     virtual off_t OnSysTell() const;
  39     virtual size_t OnSysRead(void *buffer, size_t size);
  40
  41 private:
  42     // the string we're reading from
  43     wxString m_str;
  44
  45     // position in the stream in bytes, *not* in chars
  46     size_t m_pos;
  47
  48
  49     DECLARE_NO_COPY_CLASS(wxStringInputStream)
  50 };
  51
  52 // ----------------------------------------------------------------------------
  53 // wxStringOutputStream writes data to the given string, expanding it as needed
  54 // ----------------------------------------------------------------------------
  55
  56 class WXDLLIMPEXP_BASE wxStringOutputStream : public wxOutputStream
  57 {
  58 public:
  59     // The stream will write data either to the provided string or to an
  60     // internal string which can be retrieved using GetString()
  61     wxStringOutputStream(wxString *pString = NULL)
  62     {
  63         m_str = pString ? pString : &m_strInternal;
  64         m_pos = m_str->length() / sizeof(wxChar);
  65     }
  66
  67     // get the string containing current output
  68     const wxString& GetString() const { return *m_str; }
  69
  70 protected:
  71     virtual off_t OnSysTell() const;
  72     virtual size_t OnSysWrite(const void *buffer, size_t size);
  73
  74 private:
  75     // internal string, not used if caller provided his own string
  76     wxString m_strInternal;
  77
  78     // pointer given by the caller or just pointer to m_strInternal
  79     wxString *m_str;
  80
  81     // position in the stream in bytes, *not* in chars
  82     size_t m_pos;
  83
  84
  85     DECLARE_NO_COPY_CLASS(wxStringOutputStream)
  86 };
  87
  88 #endif // wxUSE_STREAMS
  89
  90 #endif // _WX_SSTREAM_H_
  91