docs/latex/wx/filesysh.tex

   1 %
   2 % automatically generated by HelpGen from
   3 % filesystemhandler.tex at 21/Mar/99 23:00:52
   4 %
   5
   6 \section{\class{wxFileSystemHandler}}\label{wxfilesystemhandler}
   7
   8 wxFileSystemHandler (or derived classes to be exact) is used
   9 to access virtual file systems. It's public interface consists
  10 from two methods: \helpref{CanOpen}{wxfilesystemhandlercanopen}
  11 and \helpref{OpenFile}{wxfilesystemhandleropenfile}.
  12 It provides additional protected methods to simplify process
  13 of opening the file : GetProtocol, GetLeftLocation, GetRightLocation,
  14 GetAnchor, GetMimeTypeFromExt.
  15
  16 Please have a look at \helpref{overview}{fs} if you don't know how locations
  17 are constructed.
  18
  19 \wxheading{Notes}
  20
  21 \begin{itemize}
  22 \item The handlers are shared by all instances of wxFileSystem.
  23
  24 \item wxHTML library provides handlers for local files and HTTP or FTP protocol
  25
  26 \item The {\it location} parameter passed to OpenFile or CanOpen methods
  27 is always {\bf absolute} path. You don't need to check the FS's current path!
  28 \end{itemize}
  29
  30 \wxheading{Derived from}
  31
  32 wxObject
  33
  34 \wxheading{See also}
  35
  36 \helpref{wxFileSystem}{wxfilesystem},
  37 \helpref{wxFSFile}{wxfsfile},
  38 \helpref{Overview}{fs}
  39
  40 \membersection{wxFileSystemHandler::wxFileSystemHandler}\label{wxfilesystemhandlerwxfilesystemhandler}
  41
  42 \func{}{wxFileSystemHandler}{\void}
  43
  44 Constructor.
  45
  46 \membersection{wxFileSystemHandler::CanOpen}\label{wxfilesystemhandlercanopen}
  47
  48 \func{virtual bool}{CanOpen}{\param{const wxString\& }{location}}
  49
  50 Returns TRUE if the handler is able to open this file (this function doesn't
  51 check whether the file exists or not, it only checks if it knows the protocol).
  52 Example:
  53
  54 \begin{verbatim}
  55 bool MyHand::CanOpen(const wxString& location)
  56 {
  57     return (GetProtocol(location) == "http");
  58 }
  59 \end{verbatim}
  60
  61 Must be overwriten in derived handlers.
  62
  63 \membersection{wxFileSystemHandler::GetAnchor}\label{wxfilesystemhandlergetanchor}
  64
  65 \constfunc{wxString}{GetAnchor}{\param{const wxString\& }{location}}
  66
  67 Returns anchor if present in the location.
  68 See \helpref{wxFSFile}{wxfsfilegetanchor} for details.
  69
  70 Example : GetAnchor("index.htm\#chapter2") == "chapter2"
  71
  72 {\bf Note:} anchor is NOT part of left location.
  73
  74 \membersection{wxFileSystemHandler::GetLeftLocation}\label{wxfilesystemhandlergetleftlocation}
  75
  76 \constfunc{wxString}{GetLeftLocation}{\param{const wxString\& }{location}}
  77
  78 Returns left location string extracted from {\it location}.
  79
  80 Example: GetLeftLocation("file:myzipfile.zip\#zip:index.htm") == "file:myzipfile.zip"
  81
  82 \membersection{wxFileSystemHandler::GetMimeTypeFromExt}\label{wxfilesystemhandlergetmimetypefromext}
  83
  84 \func{wxString}{GetMimeTypeFromExt}{\param{const wxString\& }{location}}
  85
  86 Returns MIME type based on {\bf extension} of {\it location}. (While wxFSFile::GetMimeType
  87 returns real MIME type - either extension-based or queried from HTTP)
  88
  89 Example : GetMimeTypeFromExt("index.htm") == "text/html"
  90
  91 \membersection{wxFileSystemHandler::GetProtocol}\label{wxfilesystemhandlergetprotocol}
  92
  93 \constfunc{wxString}{GetProtocol}{\param{const wxString\& }{location}}
  94
  95 Returns protocol string extracted from {\it location}.
  96
  97 Example: GetProtocol("file:myzipfile.zip\#zip:index.htm") == "zip"
  98
  99 \membersection{wxFileSystemHandler::GetRightLocation}\label{wxfilesystemhandlergetrightlocation}
 100
 101 \constfunc{wxString}{GetRightLocation}{\param{const wxString\& }{location}}
 102
 103 Returns right location string extracted from {\it location}.
 104
 105 Example : GetRightLocation("file:myzipfile.zip\#zip:index.htm") == "index.htm"
 106
 107
 108
 109
 110
 111 \membersection{wxFileSystemHandler::FindFirst}\label{wxfilesystemfindfirst}
 112
 113 \func{virtual wxString}{FindFirst}{\param{const wxString\& }{wildcard}, \param{int }{flags = 0}}
 114
 115 Works like \helpref{wxFindFirstFile}{wxfindfirstfile}. Returns name of the first
 116 filename (withing filesystem's current path) that matches {\it wildcard}. {\it flags} may be one of
 117 wxFILE (only files), wxDIR (only directories) or 0 (both).
 118
 119 This method is only called if \helpref{CanOpen}{wxfilesystemhandlercanopen} returns TRUE.
 120
 121 \membersection{wxFileSystemHandler::FindNext}\label{wxfilesystemfindnext}
 122
 123 \func{virtual wxString}{FindNext}{\void}
 124
 125 Returns next filename that matches parameters passed to \helpref{FindFirst}{wxfilesystemfindfirst}.
 126
 127 This method is only called if \helpref{CanRead}{wxfilesystemhandlercanread} returns TRUE and FindFirst
 128 returned non-empty string.
 129
 130
 131
 132 \membersection{wxFileSystemHandler::OpenFile}\label{wxfilesystemhandleropenfile}
 133
 134 \func{virtual wxFSFile*}{OpenFile}{\param{wxFileSystem\& }{fs}, \param{const wxString\& }{location}}
 135
 136 Opens the file and returns wxFSFile pointer or NULL if failed.
 137
 138 Must be overwriten in derived handlers.
 139
 140 \wxheading{Parameters}
 141
 142 \docparam{fs}{Parent FS (the FS from that OpenFile was called). See ZIP handler
 143 for details how to use it.}
 144
 145 \docparam{location}{The {\bf absolute} location of file.}
 146