wxWidgets/interface/textfile.h
Francesco Montorsi 328f5751e8 add const qualifiers
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@52414 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
2008-03-09 16:24:26 +00:00

242 lines
8.1 KiB
Objective-C

/////////////////////////////////////////////////////////////////////////////
// Name: textfile.h
// Purpose: documentation for wxTextFile class
// Author: wxWidgets team
// RCS-ID: $Id$
// Licence: wxWindows license
/////////////////////////////////////////////////////////////////////////////
/**
@class wxTextFile
@wxheader{textfile.h}
The wxTextFile is a simple class which allows to work with text files on line by
line basis. It also understands the differences in line termination characters
under different platforms and will not do anything bad to files with "non
native" line termination sequences - in fact, it can be also used to modify the
text files and change the line termination characters from one type (say DOS) to
another (say Unix).
One word of warning: the class is not at all optimized for big files and thus
it will load the file entirely into memory when opened. Of course, you should
not
work in this way with large files (as an estimation, anything over 1 Megabyte is
surely too big for this class). On the other hand, it is not a serious
limitation for small files like configuration files or program sources
which are well handled by wxTextFile.
The typical things you may do with wxTextFile in order are:
Create and open it: this is done with either
wxTextFile::Create or wxTextFile::Open
function which opens the file (name may be specified either as the argument to
these functions or in the constructor), reads its contents in memory (in the
case of @c Open()) and closes it.
Work with the lines in the file: this may be done either with "direct
access" functions like wxTextFile::GetLineCount and
wxTextFile::GetLine (@e operator[] does exactly the same
but looks more like array addressing) or with "sequential access" functions
which include wxTextFile::GetFirstLine/
wxTextFile::GetNextLine and also
wxTextFile::GetLastLine/wxTextFile::GetPrevLine.
For the sequential access functions the current line number is maintained: it is
returned by wxTextFile::GetCurrentLine and may be
changed with wxTextFile::GoToLine.
Add/remove lines to the file: wxTextFile::AddLine and
wxTextFile::InsertLine add new lines while
wxTextFile::RemoveLine deletes the existing ones.
wxTextFile::Clear resets the file to empty.
Save your changes: notice that the changes you make to the file will @b not be
saved automatically; calling wxTextFile::Close or doing
nothing discards them! To save the changes you must explicitly call
wxTextFile::Write - here, you may also change the line
termination type if you wish.
@library{wxbase}
@category{file}
@seealso
wxFile
*/
class wxTextFile
{
public:
/**
Constructor does not load the file into memory, use Open() to do it.
*/
wxTextFile(const wxString& strFile) const;
/**
Destructor does nothing.
*/
~wxTextFile() const;
/**
Adds a line to the end of file.
*/
void AddLine(const wxString& str,
wxTextFileType type = typeDefault) const;
/**
Delete all lines from the file, set current line number to 0.
*/
void Clear() const;
/**
Closes the file and frees memory, @b losing all changes. Use Write()
if you want to save them.
*/
bool Close() const;
//@{
/**
Creates the file with the given name or the name which was given in the
@ref ctor() constructor. The array of file lines is initially
empty.
It will fail if the file already exists, Open() should
be used in this case.
*/
bool Create() const;
const bool Create(const wxString& strFile) const;
//@}
/**
Returns @true if the current line is the last one.
*/
bool Eof() const;
/**
Return @true if file exists - the name of the file should have been specified
in the constructor before calling Exists().
*/
bool Exists() const;
/**
Returns the current line: it has meaning only when you're using
GetFirstLine()/GetNextLine() functions, it doesn't get updated when
you're using "direct access" functions like GetLine(). GetFirstLine() and
GetLastLine() also change the value of the current line, as well as
GoToLine().
*/
size_t GetCurrentLine() const;
/**
Get the line termination string corresponding to given constant. @e typeDefault
is
the value defined during the compilation and corresponds to the native format
of the platform, i.e. it will be wxTextFileType_Dos under Windows,
wxTextFileType_Unix under Unix (including Mac OS X when compiling with the
Apple Developer Tools) and wxTextFileType_Mac under Mac OS (including
Mac OS X when compiling with CodeWarrior).
*/
static const char* GetEOL(wxTextFileType type = typeDefault) const;
/**
This method together with GetNextLine()
allows more "iterator-like" traversal of the list of lines, i.e. you may
write something like:
*/
wxString GetFirstLine() const;
/**
Gets the last line of the file. Together with
GetPrevLine() it allows to enumerate the lines
in the file from the end to the beginning like this:
*/
wxString GetLastLine();
/**
Retrieves the line number @a n from the file. The returned line may be
modified but you shouldn't add line terminator at the end - this will be done
by wxTextFile.
*/
wxString GetLine(size_t n) const;
/**
Get the number of lines in the file.
*/
size_t GetLineCount() const;
/**
Get the type of the line (see also wxTextFile::GetEOL)
*/
wxTextFileType GetLineType(size_t n) const;
/**
Get the name of the file.
*/
const char* GetName() const;
/**
Gets the next line (see GetFirstLine() for
the example).
*/
wxString GetNextLine();
/**
Gets the previous line in the file.
*/
wxString GetPrevLine();
/**
Changes the value returned by GetCurrentLine()
and used by wxTextFile::GetFirstLine/GetNextLine().
*/
void GoToLine(size_t n) const;
/**
Guess the type of file (which is supposed to be opened). If sufficiently
many lines of the file are in DOS/Unix/Mac format, the corresponding value will
be returned. If the detection mechanism fails wxTextFileType_None is returned.
*/
wxTextFileType GuessType() const;
/**
Insert a line before the line number @e n.
*/
void InsertLine(const wxString& str, size_t n,
wxTextFileType type = typeDefault) const;
/**
Returns @true if the file is currently opened.
*/
bool IsOpened() const;
//@{
/**
)
Open() opens the file with the given name or the name which was given in the
@ref ctor() constructor and also loads file in memory on
success. It will fail if the file does not exist,
Create() should be used in this case.
The @e conv argument is only meaningful in Unicode build of wxWidgets when
it is used to convert the file to wide character representation.
*/
bool Open() const;
const bool Open(const wxString& strFile) const;
//@}
/**
Delete line number @a n from the file.
*/
void RemoveLine(size_t n) const;
/**
)
Change the file on disk. The @a typeNew parameter allows you to change the
file format (default argument means "don't change type") and may be used to
convert, for example, DOS files to Unix.
The @e conv argument is only meaningful in Unicode build of wxWidgets when
it is used to convert all lines to multibyte representation before writing them
them to physical file.
Returns @true if operation succeeded, @false if it failed.
*/
bool Write(wxTextFileType typeNew = wxTextFileType_None) const;
/**
The same as GetLine().
*/
wxString operator[](size_t n) const;
};