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 protected:
  35     virtual size_t GetSize() const { return m_str.length(); }
  36     virtual off_t OnSysSeek(off_t ofs, wxSeekMode mode);
  37     virtual off_t OnSysTell() const;
  38     virtual size_t OnSysRead(void *buffer, size_t size);
  39
  40 private:
  41     // the string we're reading from
  42     wxString m_str;
  43
  44     // position in the stream in bytes, *not* in chars
  45     size_t m_pos;
  46
  47
  48     DECLARE_NO_COPY_CLASS(wxStringInputStream)
  49 };
  50
  51 // ----------------------------------------------------------------------------
  52 // wxStringOutputStream writes data to the given string, expanding it as needed
  53 // ----------------------------------------------------------------------------
  54
  55 class WXDLLIMPEXP_BASE wxStringOutputStream : public wxOutputStream
  56 {
  57 public:
  58     // The stream will write data either to the provided string or to an
  59     // internal string which can be retrieved using GetString()
  60     wxStringOutputStream(wxString *pString = NULL)
  61     {
  62         m_str = pString ? pString : &m_strInternal;
  63         m_pos = m_str->length() / sizeof(wxChar);
  64     }
  65
  66     // get the string containing current output
  67     const wxString& GetString() const { return *m_str; }
  68
  69 protected:
  70     virtual size_t OnSysWrite(const void *buffer, size_t size);
  71
  72 private:
  73     // internal string, not used if caller provided his own string
  74     wxString m_strInternal;
  75
  76     // pointer given by the caller or just pointer to m_strInternal
  77     wxString *m_str;
  78
  79     // position in the stream in bytes, *not* in chars
  80     size_t m_pos;
  81
  82
  83     DECLARE_NO_COPY_CLASS(wxStringOutputStream)
  84 };
  85
  86 #endif // wxUSE_STREAMS
  87
  88 #endif // _WX_SSTREAM_H_
  89