X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/bbf8fc5391b2458d630d29a794df99c8e681e6eb..8dba8632c5bcd64724e2e9e2d40e295555a0cb86:/docs/latex/wx/tokenizr.tex diff --git a/docs/latex/wx/tokenizr.tex b/docs/latex/wx/tokenizr.tex index b066262a52..0b8490ce1d 100644 --- a/docs/latex/wx/tokenizr.tex +++ b/docs/latex/wx/tokenizr.tex @@ -1,6 +1,8 @@ \section{\class{wxStringTokenizer}}\label{wxstringtokenizer} -wxStringTokenizer helps you to break a string up into a number of tokens. +wxStringTokenizer helps you to break a string up into a number of tokens. It +replaces the standard C function {\tt strtok()} and also extends it in a +number of ways. To use this class, you should create a wxStringTokenizer object, give it the string to tokenize and also the delimiters which separate tokens in the string @@ -14,7 +16,7 @@ For example: \begin{verbatim} -wxStringTokenizer tkz("first:second:third::fivth", ":"); +wxStringTokenizer tkz("first:second:third:fourth", ":"); while ( tkz.HasMoreTokens() ) { wxString token = tkz.GetNextToken(); @@ -23,14 +25,36 @@ while ( tkz.HasMoreTokens() ) } \end{verbatim} -Another feature of this class is that it may return the delimiter which -was found after the token with it. In a simple case like above, you are not -interested in this because the delimiter is always {\tt ':'}, but if the -delimiters string has several characters, you might need to know which of them -follows the current token. In this case, pass {\tt TRUE} to wxStringTokenizer -constructor or \helpref{SetString}{wxstringtokenizersetstring} method and -the delimiter will be appended to each returned token (except for the last -one). +By default, wxStringTokenizer will behave in the same way as {\tt strtok()} if +the delimiters string only contains white space characters but, unlike the +standard function, it will return empty tokens if this is not the case. This +is helpful for parsing strictly formatted data where the number of fields is +fixed but some of them may be empty (i.e. {\tt TAB} or comma delimited text +files). + +The behaviour is governed by the last +\helpref{constructor}{wxstringtokenizerwxstringtokenizer}/\helpref{SetString}{wxstringtokenizersetstring} +parameter {\tt mode} which may be one of the following: + +\twocolwidtha{5cm}% +\begin{twocollist}\itemsep=0pt +\twocolitem{{\tt wxTOKEN\_DEFAULT}}{Default behaviour (as described above): +same as {\tt wxTOKEN\_STRTOK} if the delimiter string contains only +whitespaces, same as {\tt wxTOKEN\_RET\_EMPTY} otherwise} +\twocolitem{{\tt wxTOKEN\_RET\_EMPTY}}{In this mode, the empty tokens in the +middle of the string will be returned, i.e. {\tt "a::b:"} will be tokenized in +three tokens `a', `' and `b'.} +\twocolitem{{\tt wxTOKEN\_RET\_EMPTY\_ALL}}{In this mode, empty trailing token +(after the last delimiter character) will be returned as well. The string as +above will contain four tokens: the already mentioned ones and another empty +one as the last one.} +\twocolitem{{\tt wxTOKEN\_RET\_DELIMS}}{In this mode, the delimiter character +after the end of the current token (there may be none if this is the last +token) is returned appended to the token. Otherwise, it is the same mode as +{\tt wxTOKEN\_RET\_EMPTY}.} +\twocolitem{{\tt wxTOKEN\_STRTOK}}{In this mode the class behaves exactly like +the standard {\tt strtok()} function. The empty tokens are never returned.} +\end{twocollist} \wxheading{Derived from} @@ -46,18 +70,14 @@ one). \func{}{wxStringTokenizer}{\void} -Default constructor. +Default constructor. You must call +\helpref{SetString}{wxstringtokenizersetstring} before calling any other +methods. -\func{}{wxStringTokenizer}{\param{const wxString\& }{to\_tokenize}, \param{const wxString\& }{delims = " $\backslash$t$\backslash$r$\backslash$n"}, \param{bool }{ret\_delim = FALSE}} +\func{}{wxStringTokenizer}{\param{const wxString\& }{str}, \param{const wxString\& }{delims = " $\backslash$t$\backslash$r$\backslash$n"}, \param{wxStringTokenizerMode }{mode = wxTOKEN\_DEFAULT}} -Constructor. Pass the string to tokenize, a string containing delimiters, -a flag specifying whether to return delimiters with tokens. - -\membersection{wxStringTokenizer::\destruct{wxStringTokenizer}}\label{wxstringtokenizerdtor} - -\func{}{\destruct{wxStringTokenizer}}{\void} - -Destructor. +Constructor. Pass the string to tokenize, a string containing delimiters +and the mode specifying how the string should be tokenized. \membersection{wxStringTokenizer::CountTokens}\label{wxstringtokenizercounttokens} @@ -69,11 +89,11 @@ Returns the number of tokens in the input string. \constfunc{bool}{HasMoreTokens}{\void} -Returns TRUE if the tokenizer has further tokens. +Returns TRUE if the tokenizer has further tokens, FALSE if none are left. \membersection{wxStringTokenizer::GetNextToken}\label{wxstringtokenizergetnexttoken} -\constfunc{wxString}{GetNextToken}{\void} +\func{wxString}{GetNextToken}{\void} Returns the next token or empty string if the end of string was reached. @@ -93,10 +113,10 @@ Returns the part of the starting string without all token already extracted. \membersection{wxStringTokenizer::SetString}\label{wxstringtokenizersetstring} -\func{void}{SetString}{\param{const wxString\& }{to\_tokenize}, \param{const wxString\& }{delims = " $\backslash$t$\backslash$r$\backslash$n"}, \param{bool }{ret\_delim = FALSE}} +\func{void}{SetString}{\param{const wxString\& }{to\_tokenize}, \param{const wxString\& }{delims = " $\backslash$t$\backslash$r$\backslash$n"}, \param{wxStringTokenizerMode }{mode = wxTOKEN\_DEFAULT}} Initializes the tokenizer. Pass the string to tokenize, a string containing delimiters, -a flag specifying whether to return delimiters with tokens. +and the mode specifying how the string should be tokenized.