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 @a 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 @a copies of the new item @a str to the
  80         array and returns the index of the first new item in the array.
  81         @b Warning: For sorted arrays, the index of the inserted item will not be,
  82         in general, equal to GetCount() - 1 because
  83         the item is inserted at the correct position to keep the array sorted and not
  84         appended.
  85         See also: Insert()
  86     */
  87     size_t Add(const wxString& str, size_t copies = 1);
  88
  89     /**
  90         Preallocates enough memory to store @a nCount items. This function may be
  91         used to improve array class performance before adding a known number of items
  92         consecutively.
  93         See also: @ref wxArray::memorymanagement "Dynamic array memory management"
  94     */
  95     void Alloc(size_t nCount);
  96
  97     /**
  98         Clears the array contents and frees memory.
  99         See also: Empty()
 100     */
 101     void Clear();
 102
 103     /**
 104         Empties the array: after a call to this function
 105         GetCount() will return 0. However, this
 106         function does not free the memory used by the array and so should be used when
 107         the array is going to be reused for storing other strings. Otherwise, you
 108         should use Clear() to empty the array and free
 109         memory.
 110     */
 111     void Empty();
 112
 113     /**
 114         Returns the number of items in the array.
 115     */
 116     size_t GetCount() const;
 117
 118     /**
 119         Search the element in the array, starting from the beginning if
 120         @a bFromEnd is @false or from end otherwise. If @e bCase, comparison is
 121         case sensitive (default), otherwise the case is ignored.
 122         This function uses linear search for wxArrayString and binary search for
 123         wxSortedArrayString, but it ignores the @a bCase and @a bFromEnd
 124         parameters in the latter case.
 125         Returns index of the first item matched or @c wxNOT_FOUND if there is no match.
 126     */
 127     int Index(const wxString& sz, bool bCase = true,
 128               bool bFromEnd = false);
 129
 130     /**
 131         Insert the given number of @a copies of the new element in the array before the
 132         position @e nIndex. Thus, for
 133         example, to insert the string in the beginning of the array you would write
 134
 135         If @a nIndex is equal to @e GetCount() this function behaves as
 136         Add().
 137         @b Warning: this function should not be used with sorted arrays because it
 138         could break the order of items and, for example, subsequent calls to
 139         Index() would then not work!
 140     */
 141     void Insert(const wxString& str, size_t nIndex,
 142                 size_t copies = 1);
 143
 144     /**
 145         Returns @true if the array is empty, @false otherwise. This function returns the
 146         same result as @e GetCount() == 0 but is probably easier to read.
 147     */
 148     bool IsEmpty();
 149
 150     /**
 151         Return the array element at position @e nIndex. An assert failure will
 152         result from an attempt to access an element beyond the end of array in debug
 153         mode, but no check is done in release mode.
 154         See also @ref operatorindex() operator[] for the operator
 155         version.
 156     */
 157     wxString Item(size_t nIndex) const;
 158
 159     /**
 160         Returns the last element of the array. Attempt to access the last element of
 161         an empty array will result in assert failure in debug build, however no checks
 162         are done in release mode.
 163     */
 164     wxString Last();
 165
 166     /**
 167         Removes the first item matching this value. An assert failure is provoked by
 168         an attempt to remove an element which does not exist in debug build.
 169         See also: Index()
 170     */
 171     void Remove(const wxString& sz);
 172
 173     /**
 174         Removes @a count items starting at position @a nIndex from the array.
 175     */
 176     void RemoveAt(size_t nIndex, size_t count = 1);
 177
 178     /**
 179         Releases the extra memory allocated by the array. This function is useful to
 180         minimize the array memory consumption.
 181         See also: Alloc(), @ref wxArray::memorymanagement "Dynamic array memory
 182         management"
 183     */
 184     void Shrink();
 185
 186     //@{
 187     /**
 188         Sorts the array using the specified @a compareFunction for item comparison.
 189         @e CompareFunction is defined as a function taking two @e const
 190         wxString parameters and returning an @e int value less than, equal to or
 191         greater than 0 if the first string is less than, equal to or greater than the
 192         second one.
 193     */
 194     void Sort(bool reverseOrder = false);
 195 Warning:
 196     void Sort(CompareFunction compareFunction);
 197     //@}
 198
 199     /**
 200         Compares 2 arrays respecting the case. Returns @true if the arrays have
 201         different number of elements or if the elements don't match pairwise.
 202     */
 203     bool operator !=(const wxArrayString& array) const;
 204
 205     /**
 206         Assignment operator.
 207     */
 208     wxArrayString operator =(const wxArrayString& array);
 209
 210     /**
 211         Compares 2 arrays respecting the case. Returns @true only if the arrays have
 212         the same number of elements and the same strings in the same order.
 213     */
 214     bool operator ==(const wxArrayString& array) const;
 215
 216     /**
 217         Return the array element at position @e nIndex. An assert failure will
 218         result from an attempt to access an element beyond the end of array in debug
 219         mode, but no check is done in release mode.
 220         This is the operator version of Item() method.
 221     */
 222     wxString operator[](size_t nIndex);
 223 };
 224
 225
 226 // ============================================================================
 227 // Global functions/macros
 228 // ============================================================================
 229
 230 /**
 231     Splits the given wxString object using the separator @a sep and returns the
 232     result as a wxArrayString.
 233     If the @a escape character is non-@NULL, then the occurrences of @a sep
 234     immediately prefixed
 235     with @a escape are not considered as separators.
 236     Note that empty tokens will be generated if there are two or more adjacent
 237     separators.
 238
 239     @see wxJoin
 240 */
 241 wxArrayString wxSplit(const wxString& str, const wxChar sep,
 242                       const wxChar escape = '
 243                                             ');
 244
 245 /**
 246     Concatenate all lines of the given wxArrayString object using the separator @a
 247     sep and returns
 248     the result as a wxString.
 249     If the @a escape character is non-@NULL, then it's used as prefix for each
 250     occurrence of @e sep
 251     in the strings contained in @a arr before joining them which is necessary
 252     in order to be able to recover the original array contents from the string
 253     later using wxSplit.
 254 */
 255 wxString wxJoin(const wxArrayString& arr, const wxChar sep,
 256                 const wxChar escape = '\');
 257