how to turn on multiline option of boost::regex_search() algorithm
Can any one tell me how to specify "Multiline" search while using regex? e.g. std::string fb; // fb stores a fragment of html code, multiline; boost::regex pattern("</tr>\r\n</table>\r\n</td>\r\n</tr>\r\n</table>\r\n</td>\r\n</tr>\r\n</table>"); boost::smatch res; boost::match_flag_type flags = boost::match_default; std::string::const_iterator s , e; s = fb.begin(); e = fb.end(); if(boost::regex_search(s, e, res, pattern, flags)) { //process the match. } else { //I am always here } When I use some other regex tools to check the same target string and match pattern string, I always get the right thing as expected. How can I alter the option of boost::regex_search to satisfy the original request? thanks -- This is my Very Signature. Ha, pretty good?
Hi, This is not really an answer to your question (since I don't know either :-) ), but it might help nonetheless. cr/lf are always a bit problematic (is it \n or \r\n, what's in the input string, does the engine do platform dependent conversions, etc) and not really important in HTML since it's just whitespace. For this reason, instead of matching a line-break, I match whitespace. This also handles indentations correctly. Therefore, I'd use the pattern: "</tr>\s*</table>\s*</td>\s*</tr>\s*</table>\s*</td>\s*</tr>\s*</table>" good luck, agb
Can any one tell me how to specify "Multiline" search while using regex?
e.g.
std::string fb; // fb stores a fragment of html code, multiline; boost::regex pattern("</tr>\r\n</table>\r\n</td>\r\n</tr>\r\n</table>\r\n</td>\r\n</tr>\r\n</table>"); boost::smatch res; boost::match_flag_type flags = boost::match_default; std::string::const_iterator s , e; s = fb.begin(); e = fb.end(); if(boost::regex_search(s, e, res, pattern, flags)) { //process the match. } else { //I am always here }
When I use some other regex tools to check the same target string and match pattern string, I always get the right thing as expected. How can I alter the option of boost::regex_search to satisfy the original request? thanks
-- This is my Very Signature. Ha, pretty good? _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users
Hi,
This is not really an answer to your question (since I don't know either :-) ), but it might help nonetheless. cr/lf are always a bit problematic (is it \n or \r\n, what's in the input string, does the engine do platform dependent conversions, etc) and not really important in HTML since it's just whitespace. For this reason, instead of matching a line-break, I match whitespace. This also handles indentations correctly. Therefore, I'd use the pattern:
"</tr>\s*</table>\s*</td>\s*</tr>\s*</table>\s*</td>\s*</tr>\s*</table>"
good luck,
agb
Can any one tell me how to specify "Multiline" search while using regex?
e.g.
std::string fb; // fb stores a fragment of html code, multiline; boost::regex
works, thanks a lot
well I found under windows platform, pattern "\\n" can just satisfy my
request.
(say, to match exactly a line-break)
anyway, thanks.
On 6/13/06, Anne-Gert Bultena
boost::smatch res; boost::match_flag_type flags = boost::match_default; std::string::const_iterator s , e; s = fb.begin(); e = fb.end(); if(boost::regex_search(s, e, res, pattern, flags)) { //process the match. } else { //I am always here }
When I use some other regex tools to check the same target string and match pattern string, I always get the right thing as expected. How can I alter the option of boost::regex_search to satisfy the original request? thanks
-- This is my Very Signature. Ha, pretty good? _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users
_______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users
-- This is my Very Signature. Ha, pretty good?
important in HTML since it's just whitespace. For this reason, instead of matching a line-break, I match whitespace. This also handles indentations correctly. Therefore, I'd use the pattern:
"</tr>\s*</table>\s*</td>\s*</tr>\s*</table>\s*</td>\s*</tr>\s*</table>"
Right but those \'s need to be doubled up to be used in a C++ string: remember the compiler swallows up the first \ so use "</tr>\\s*</table>\\s*</td>\\s*</tr>\\s*</table>\\s*</td>\\s*</tr>\\s*</table>" John.
Renjie Zhao wrote:
Can any one tell me how to specify "Multiline" search while using regex?
Multiline is the default. I suggest you verify that your string actually has \r's in it: if it has been read in with std iostreams it most certainly will not. John.
participants (3)
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Anne-Gert Bultena -
John Maddock -
Renjie Zhao