interface/arrstr.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        arrstr.h
   3 // Purpose:     interface of wxArrayString
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxArrayString
  11     @wxheader{arrstr.h}
  12
  13     wxArrayString is an efficient container for storing wxString objects.
  14
  15     It has the same features as all wxArray classes, i.e. it dynamically expands
  16     when new items are added to it (so it is as easy to use as a linked list),
  17     but the access time to the elements is constant, instead of being linear in
  18     number of elements as in the case of linked lists. It is also very size
  19     efficient and doesn't take more space than a C array @e wxString[] type
  20     (wxArrayString uses its knowledge of internals of wxString class to achieve this).
  21
  22     This class is used in the same way as other dynamic arrays(), except that no
  23     @e WX_DEFINE_ARRAY declaration is needed for it.
  24     When a string is added or inserted in the array, a copy of the string is created,
  25     so the original string may be safely deleted (e.g. if it was a @e wxChar *
  26     pointer the memory it was using can be freed immediately after this).
  27     In general, there is no need to worry about string memory deallocation when using
  28     this class - it will always free the memory it uses itself.
  29
  30     The references returned by wxArrayString::Item, wxArrayString::Last or
  31     wxArrayString::operator[] are not constant, so the array elements may
  32     be modified in place like this:
  33
  34     @code
  35     array.Last().MakeUpper();
  36     @endcode
  37
  38     There is also a variant of wxArrayString called wxSortedArrayString which has
  39     exactly the same methods as wxArrayString, but which always keeps the string
  40     in it in (alphabetical) order. wxSortedArrayString uses binary search in its
  41     wxArrayString::Index() function (instead of linear search for wxArrayString::Index())
  42     which makes it much more efficient if you add strings to the array rarely
  43     (because, of course, you have to pay for Index() efficiency by having Add() be
  44     slower) but search for them often. Several methods should not be used with
  45     sorted array (basically, all which break the order of items) which is
  46     mentioned in their description.
  47
  48     @note none of the methods of wxArrayString is virtual including its
  49           destructor, so this class should not be used as a base class.
  50
  51     Although this is not true strictly speaking, this class may be considered as
  52     a specialization of wxArray class for the wxString member data: it is not
  53     implemented like this, but it does have all of the wxArray functions.
  54
  55     @library{wxbase}
  56     @category{containers}
  57
  58     @see wxArray, wxString, @ref overview_string
  59 */
  60 class wxArrayString : public wxArray
  61 {
  62 public:
  63     /**
  64         Default constructor.
  65     */
  66     wxArrayString();
  67
  68     /**
  69         Copy constructor. Note that when an array is assigned to a sorted array,
  70         its contents is automatically sorted during construction.
  71     */
  72     wxArrayString(const wxArrayString& array);
  73
  74     //@{
  75     /**
  76         Constructor from a C string array. Pass a size sz and array arr.
  77     **/
  78     wxArrayString(size_t sz, const char** arr);
  79     wxArrayString(size_t sz, const wchar_t** arr);
  80     //@}
  81
  82     /**
  83         Constructor from a wxString array. Pass a size @a sz and array @e arr.
  84     */
  85     wxArrayString(size_t sz, const wxString* arr);
  86
  87     /**
  88         Destructor frees memory occupied by the array strings. For performance
  89         reasons it is not virtual, so this class should not be derived from.
  90     */
  91     ~wxArrayString();
  92
  93     /**
  94         Appends the given number of @a copies of the new item @a str to the
  95         array and returns the index of the first new item in the array.
  96
  97         @warning
  98         For sorted arrays, the index of the inserted item will not be, in general,
  99         equal to GetCount() - 1 because the item is inserted at the correct position
 100         to keep the array sorted and not appended.
 101
 102         @see Insert()
 103     */
 104     size_t Add(const wxString& str, size_t copies = 1);
 105
 106     /**
 107         Preallocates enough memory to store @a nCount items. This function may be
 108         used to improve array class performance before adding a known number of items
 109         consecutively.
 110
 111         @todo FIX THIS LINK
 112
 113         @see @ref wxArray::memorymanagement "Dynamic array memory management"
 114     */
 115     void Alloc(size_t nCount);
 116
 117     /**
 118         Clears the array contents and frees memory.
 119
 120         @see Empty()
 121     */
 122     void Clear();
 123
 124     /**
 125         Empties the array: after a call to this function GetCount() will return 0.
 126         However, this function does not free the memory used by the array and so
 127         should be used when the array is going to be reused for storing other strings.
 128         Otherwise, you should use Clear() to empty the array and free memory.
 129     */
 130     void Empty();
 131
 132     /**
 133         Returns the number of items in the array.
 134     */
 135     size_t GetCount() const;
 136
 137     /**
 138         Search the element in the array, starting from the beginning if @a bFromEnd
 139         is @false or from end otherwise. If @e bCase, comparison is case sensitive
 140         (default), otherwise the case is ignored.
 141
 142         This function uses linear search for wxArrayString and binary search for
 143         wxSortedArrayString, but it ignores the @a bCase and @a bFromEnd parameters
 144         in the latter case.
 145         Returns index of the first item matched or @c wxNOT_FOUND if there is no match.
 146     */
 147     int Index(const wxString& sz, bool bCase = true,
 148               bool bFromEnd = false);
 149
 150     /**
 151         Insert the given number of @a copies of the new element in the array before the
 152         position @e nIndex. Thus, for example, to insert the string in the beginning of
 153         the array you would write:
 154
 155         @code
 156         Insert("foo", 0);
 157         @endcode
 158
 159         If @a nIndex is equal to @e GetCount() this function behaves as Add().
 160
 161         @warning this function should not be used with sorted arrays because it
 162                  could break the order of items and, for example, subsequent calls
 163                  to Index() would then not work!
 164     */
 165     void Insert(const wxString& str, size_t nIndex,
 166                 size_t copies = 1);
 167
 168     /**
 169         Returns @true if the array is empty, @false otherwise. This function returns the
 170         same result as @e GetCount() == 0 but is probably easier to read.
 171     */
 172     bool IsEmpty();
 173
 174     /**
 175         Return the array element at position @e nIndex. An assert failure will
 176         result from an attempt to access an element beyond the end of array in debug
 177         mode, but no check is done in release mode.
 178
 179         @see operator[] for the operator version.
 180     */
 181     wxString Item(size_t nIndex) const;
 182
 183     /**
 184         Returns the last element of the array. Attempt to access the last element of
 185         an empty array will result in assert failure in debug build, however no checks
 186         are done in release mode.
 187     */
 188     wxString Last();
 189
 190     /**
 191         Removes the first item matching this value. An assert failure is provoked by
 192         an attempt to remove an element which does not exist in debug build.
 193
 194         @see Index()
 195     */
 196     void Remove(const wxString& sz);
 197
 198     /**
 199         Removes @a count items starting at position @a nIndex from the array.
 200     */
 201     void RemoveAt(size_t nIndex, size_t count = 1);
 202
 203     /**
 204         Releases the extra memory allocated by the array. This function is useful to
 205         minimize the array memory consumption.
 206
 207         @todo FIX THIS LINK
 208
 209         @see Alloc(), @ref wxArray::memorymanagement "Dynamic array memory
 210         management"
 211     */
 212     void Shrink();
 213
 214     /**
 215         Sorts the array in alphabetical order or in reverse alphabetical order if
 216         @a reverseOrder is @true. The sort is case-sensitive.
 217
 218         @warning this function should not be used with sorted array because it could
 219                  break the order of items and, for example, subsequent calls to Index()
 220                  would then not work!
 221     */
 222
 223     void Sort(bool reverseOrder = false);
 224
 225     /**
 226         Sorts the array using the specified @a compareFunction for item comparison.
 227         @e CompareFunction is defined as a function taking two @e const wxString
 228         parameters and returning an @e int value less than, equal to or greater
 229         than 0 if the first string is less than, equal to or greater than the
 230         second one.
 231
 232         Example:
 233         The following example sorts strings by their length.
 234
 235         @code
 236         static int CompareStringLen(const wxString& first, const wxString& second)
 237         {
 238             return first.length() - second.length();
 239         }
 240
 241         ...
 242
 243         wxArrayString array;
 244
 245         array.Add("one");
 246         array.Add("two");
 247         array.Add("three");
 248         array.Add("four");
 249
 250         array.Sort(CompareStringLen);
 251         @endcode
 252
 253         @warning this function should not be used with sorted array because
 254                  it could break the order of items and, for example, subsequent
 255                  calls to Index() would then not work!
 256     */
 257     void Sort(CompareFunction compareFunction);
 258
 259     /**
 260         Compares 2 arrays respecting the case. Returns @true if the arrays have
 261         different number of elements or if the elements don't match pairwise.
 262     */
 263     bool operator !=(const wxArrayString& array) const;
 264
 265     /**
 266         Assignment operator.
 267     */
 268     wxArrayString operator =(const wxArrayString& array);
 269
 270     /**
 271         Compares 2 arrays respecting the case. Returns @true only if the arrays have
 272         the same number of elements and the same strings in the same order.
 273     */
 274     bool operator ==(const wxArrayString& array) const;
 275
 276     /**
 277         Return the array element at position @e nIndex. An assert failure will
 278         result from an attempt to access an element beyond the end of array in
 279         debug mode, but no check is done in release mode.
 280
 281         This is the operator version of the Item() method.
 282     */
 283     wxString operator[](size_t nIndex);
 284 };
 285
 286
 287
 288 // ============================================================================
 289 // Global functions/macros
 290 // ============================================================================
 291
 292 /** @ingroup group_funcmacro_string */
 293 //@{
 294
 295 /**
 296     Splits the given wxString object using the separator @a sep and returns the
 297     result as a wxArrayString.
 298
 299     If the @a escape character is non-@NULL, then the occurrences of @a sep
 300     immediately prefixed with @a escape are not considered as separators.
 301     Note that empty tokens will be generated if there are two or more adjacent
 302     separators.
 303
 304     @see wxJoin()
 305 */
 306 wxArrayString wxSplit(const wxString& str, const wxChar sep,
 307                       const wxChar escape = '\\');
 308
 309 /**
 310     Concatenate all lines of the given wxArrayString object using the separator
 311     @a sep and returns the result as a wxString.
 312
 313     If the @a escape character is non-@NULL, then it's used as prefix for each
 314     occurrence of @e sep in the strings contained in @a arr before joining them
 315     which is necessary in order to be able to recover the original array contents
 316     from the string later using wxSplit().
 317
 318     @see wxSplit()
 319 */
 320 wxString wxJoin(const wxArrayString& arr, const wxChar sep,
 321                 const wxChar escape = '\\');
 322
 323 //@}