interface/arrstr.h

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