interface/wx/tokenzr.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        tokenzr.h
   3 // Purpose:     interface of wxStringTokenizer
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     The behaviour of wxStringTokenizer is governed by the
  11     wxStringTokenizer::wxStringTokenizer() or wxStringTokenizer::SetString()
  12     with the parameter @e mode, which may be one of the following:
  13 */
  14 enum wxStringTokenizerMode
  15 {
  16     wxTOKEN_INVALID = -1,   ///< Invalid tokenizer mode.
  17
  18     /**
  19         Default behaviour: wxStringTokenizer will behave in the same way as
  20         @c strtok() (::wxTOKEN_STRTOK) if the delimiters string only contains
  21         white space characters but, unlike the standard function, it will
  22         behave like ::wxTOKEN_RET_EMPTY, returning empty tokens if this is not
  23         the case. This is helpful for parsing strictly formatted data where
  24         the number of fields is fixed but some of them may be empty (i.e.
  25         @c TAB or comma delimited text files).
  26     */
  27     wxTOKEN_DEFAULT,
  28
  29     /**
  30         In this mode, the empty tokens in the middle of the string will be returned,
  31         i.e. @c "a::b:" will be tokenized in three tokens @c 'a', " and @c 'b'. Notice
  32         that all trailing delimiters are ignored in this mode, not just the last one,
  33         i.e. a string @c "a::b::" would still result in the same set of tokens.
  34     */
  35     wxTOKEN_RET_EMPTY,
  36
  37     /**
  38         In this mode, empty trailing tokens (including the one after the last delimiter
  39         character) will be returned as well. The string @c "a::b:" will be tokenized in
  40         four tokens: the already mentioned ones and another empty one as the last one
  41         and a string @c "a::b::" will have five tokens.
  42     */
  43     wxTOKEN_RET_EMPTY_ALL,
  44
  45     /**
  46         In this mode, the delimiter character after the end of the current token (there
  47         may be none if this is the last token) is returned appended to the token.
  48         Otherwise, it is the same mode as ::wxTOKEN_RET_EMPTY. Notice that there is no
  49         mode like this one but behaving like ::wxTOKEN_RET_EMPTY_ALL instead of
  50         ::wxTOKEN_RET_EMPTY, use ::wxTOKEN_RET_EMPTY_ALL and
  51         wxStringTokenizer::GetLastDelimiter() to emulate it.
  52     */
  53     wxTOKEN_RET_DELIMS,
  54
  55     /**
  56         In this mode the class behaves exactly like the standard @c strtok() function:
  57         the empty tokens are never returned.
  58     */
  59     wxTOKEN_STRTOK
  60 };
  61
  62 /**
  63     @class wxStringTokenizer
  64
  65     wxStringTokenizer helps you to break a string up into a number of tokens.
  66     It replaces the standard C function @c strtok() and also extends it in a
  67     number of ways.
  68
  69     To use this class, you should create a wxStringTokenizer object, give it the
  70     string to tokenize and also the delimiters which separate tokens in the string
  71     (by default, white space characters will be used).
  72
  73     Then wxStringTokenizer::GetNextToken() may be called repeatedly until
  74     wxStringTokenizer::HasMoreTokens() returns @false.
  75
  76     For example:
  77
  78     @code
  79     wxStringTokenizer tokenizer("first:second:third:fourth", ":");
  80     while ( tokenizer.HasMoreTokens() )
  81     {
  82         wxString token = tokenizer.GetNextToken();
  83
  84         // process token here
  85     }
  86     @endcode
  87
  88     @library{wxbase}
  89     @category{data}
  90
  91     @see wxStringTokenize()
  92 */
  93 class wxStringTokenizer : public wxObject
  94 {
  95 public:
  96     /**
  97         Default constructor. You must call SetString() before calling any other
  98         methods.
  99     */
 100     wxStringTokenizer();
 101     /**
 102         Constructor. Pass the string to tokenize, a string containing
 103         delimiters, and the @a mode specifying how the string should be
 104         tokenized.
 105
 106         @see SetString()
 107    */
 108     wxStringTokenizer(const wxString& str,
 109                       const wxString& delims = " \t\r\n",
 110                       wxStringTokenizerMode mode = wxTOKEN_DEFAULT);
 111
 112     /**
 113         Returns the number of tokens remaining in the input string. The number
 114         of tokens returned by this function is decremented each time
 115         GetNextToken() is called and when it reaches 0, HasMoreTokens()
 116         returns @false.
 117     */
 118     size_t CountTokens() const;
 119
 120     /**
 121         Returns the delimiter which ended scan for the last token returned by
 122         GetNextToken() or @c NUL if there had been no calls to this function
 123         yet or if it returned the trailing empty token in
 124         ::wxTOKEN_RET_EMPTY_ALL mode.
 125
 126         @since 2.7.0
 127     */
 128     wxChar GetLastDelimiter() const;
 129
 130     /**
 131         Returns the next token or empty string if the end of string was reached.
 132     */
 133     wxString GetNextToken();
 134
 135     /**
 136         Returns the current position (i.e. one index after the last returned
 137         token or 0 if GetNextToken() has never been called) in the original
 138         string.
 139     */
 140     size_t GetPosition() const;
 141
 142     /**
 143         Returns the part of the starting string without all token already extracted.
 144     */
 145     wxString GetString() const;
 146
 147     /**
 148         Returns @true if the tokenizer has further tokens, @false if none are left.
 149     */
 150     bool HasMoreTokens() const;
 151
 152     /**
 153         Initializes the tokenizer. Pass the string to tokenize, a string
 154         containing delimiters, and the @a mode specifying how the string
 155         should be tokenized.
 156     */
 157     void SetString(const wxString& to_tokenize,
 158                    const wxString& delims = " \t\r\n",
 159                    wxStringTokenizerMode mode = wxTOKEN_DEFAULT);
 160 };