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