wxWidgets/include/wx/html/htmlparser.h
Václav Slavík 5526e819ec *** empty log message ***
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@2963 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
1999-07-07 22:04:58 +00:00

177 lines
7.2 KiB
C++

/////////////////////////////////////////////////////////////////////////////
// Name: htmlparser.h
// Purpose: wxHtmlParser class (generic parser)
// Author: Vaclav Slavik
// Copyright: (c) 1999 Vaclav Slavik
// Licence: wxWindows Licence
/////////////////////////////////////////////////////////////////////////////
#ifndef __HTMLPARSER_H__
#define __HTMLPARSER_H__
#ifdef __GNUG__
#pragma interface
#endif
#include "wx/defs.h"
#if wxUSE_HTML
#include <wx/html/htmltag.h>
#include <wx/filesys.h>
class wxHtmlParser;
class wxHtmlTagHandler;
//--------------------------------------------------------------------------------
// wxHtmlParser
// This class handles generic parsing of HTML document : it scans
// the document and divide it into blocks of tags (where one block
// consists of starting and ending tag and of text between these
// 2 tags.
//--------------------------------------------------------------------------------
class WXDLLEXPORT wxHtmlParser : public wxObject
{
DECLARE_ABSTRACT_CLASS(wxHtmlParser)
protected:
wxString m_Source;
// source being parsed
wxHtmlTagsCache *m_Cache;
// tags cache, used during parsing.
wxHashTable m_HandlersHash;
wxList m_HandlersList;
// handlers that handle particular tags. The table is accessed by
// key = tag's name.
// This attribute MUST be filled by derived class otherwise it would
// be empty and no tags would be recognized
// (see wxHtmlWinParser for details about filling it)
// m_HandlersHash is for random access based on knowledge of tag name (BR, P, etc.)
// it may (and often does) contain more references to one object
// m_HandlersList is list of all handlers and it is guaranteed to contain
// only one reference to each handler instance.
wxFileSystem *m_FS;
// class for opening files (file system)
public:
wxHtmlParser() : wxObject(), m_HandlersHash(wxKEY_STRING) {m_FS = NULL; m_Cache = NULL;}
virtual ~wxHtmlParser();
void SetFS(wxFileSystem *fs) {m_FS = fs;}
// Sets the class which will be used for opening files
wxFileSystem* GetFS() const {return m_FS;}
wxObject* Parse(const wxString& source);
// You can simply call this method when you need parsed output.
// This method does these things:
// 1. call InitParser(source);
// 2. call DoParsing();
// 3. call GetProduct(); (it's return value is then returned)
// 4. call DoneParser();
virtual void InitParser(const wxString& source);
// Sets the source. This must be called before running Parse() method.
virtual void DoneParser();
// This must be called after Parse().
void DoParsing(int begin_pos, int end_pos);
inline void DoParsing() {DoParsing(0, m_Source.Length());};
// Parses the m_Source from begin_pos to end_pos-1.
// (in noparams version it parses whole m_Source)
virtual wxObject* GetProduct() = 0;
// Returns product of parsing
// Returned value is result of parsing of the part. The type of this result
// depends on internal representation in derived parser
// (see wxHtmlWinParser for details).
virtual void AddTagHandler(wxHtmlTagHandler *handler);
// adds handler to the list & hash table of handlers.
wxString* GetSource() {return &m_Source;}
virtual wxList* GetTempData() {return NULL;}
// this method returns list of wxObjects that represents
// all data allocated by the parser. These can't be freeded
// by destructor because they must be valid as long as
// GetProduct's return value is valid - the caller must
// explicitly call delete MyParser -> GetTempData() to free
// the memory
// (this method always sets the list to delete its contents)
protected:
virtual void AddText(const char* txt) = 0;
// Adds text to the output.
// This is called from Parse() and must be overriden in derived classes.
// txt is not guaranteed to be only one word. It is largest continuous part of text
// (= not broken by tags)
// NOTE : using char* because of speed improvements
virtual void AddTag(const wxHtmlTag& tag);
// Adds tag and proceeds it. Parse() may (and usually is) called from this method.
// This is called from Parse() and may be overriden.
// Default behavior is that it looks for proper handler in m_Handlers. The tag is
// ignored if no hander is found.
// Derived class is *responsible* for filling in m_Handlers table.
};
//--------------------------------------------------------------------------------
// wxHtmlTagHandler
// This class (and derived classes) cooperates with wxHtmlParser.
// Each recognized tag is passed to handler which is capable
// of handling it. Each tag is handled in 3 steps:
// 1. Handler will modifies state of parser
// (using it's public methods)
// 2. Parser parses source between starting and ending tag
// 3. Handler restores original state of the parser
//--------------------------------------------------------------------------------
class WXDLLEXPORT wxHtmlTagHandler : public wxObject
{
DECLARE_ABSTRACT_CLASS(wxHtmlTagHandler)
protected:
wxHtmlParser *m_Parser;
public:
wxHtmlTagHandler() : wxObject () {m_Parser = NULL;};
virtual void SetParser(wxHtmlParser *parser) {m_Parser = parser;}
// Sets the parser.
// NOTE : each _instance_ of handler is guaranteed to be called
// only by one parser. This means you don't have to care about
// reentrancy.
virtual wxString GetSupportedTags() = 0;
// Returns list of supported tags. The list is in uppercase and
// tags are delimited by ','.
// Example : "I,B,FONT,P"
// is capable of handling italic, bold, font and paragraph tags
virtual bool HandleTag(const wxHtmlTag& tag) = 0;
// This is hadling core method. It does all the Steps 1-3.
// To process step 2, you can call ParseInner()
// returned value : TRUE if it called ParseInner(),
// FALSE etherwise
protected:
void ParseInner(const wxHtmlTag& tag) {m_Parser -> DoParsing(tag.GetBeginPos(), tag.GetEndPos1());}
// parses input between beginning and ending tag.
// m_Parser must be set.
};
#endif // __HTMLPARSER_H__
#endif