wxArrayString documentation added
[wxWidgets.git] / docs / latex / wx / arrstrng.tex
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 sue 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 char *}
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 Finally, none of the methods of this class is virtual including its
30 destructor, so this class should not be derived from.
31
32 \wxheading{Specialization of}
33
34 Although this is not true strictly speaking, this class may be considered as a
35 specialization of \helpref{wxArray}{wxarray} class for the wxString member
36 data: it is not implemented like this, but it does have all of the wxArray
37 functions.
38
39 \wxheading{Include files}
40
41 <wx/string.h>
42
43 \wxheading{See also}
44
45 \helpref{wxArray}{wxarray}, \helpref{wxString}{wxstring}, \helpref{wxString
46 overview}{wxstringoverview}
47
48 \latexignore{\rtfignore{\wxheading{Members}}}
49
50 \membersection{wxArrayString::wxArrayString}\label{wxarraystringctor}
51
52 \func{}{wxArrayString}{\void}
53
54 \func{}{wxArrayString}{\param{const wxArrayString\&}{ array}}
55
56 Default and copy constructors.
57
58 \membersection{wxArrayString::\destruct{wxArrayString}}\label{wxarraystringdtor}
59
60 \func{}{\destruct{wxArrayString}}{}
61
62 Destructor frees memory occupied by the array strings. For the performance
63 reasons it is not virtual, so this class should not be derived from.
64
65 \membersection{wxArrayString::operator=}\label{wxarraystringoperatorassign}
66
67 \func{wxArrayString \&}{operator $=$}{\param{const wxArrayString\&}{ array}}
68
69 Assignment operator.
70
71 \membersection{wxArrayString::operator[]}\label{wxarraystringoperatorindex}
72
73 \func{wxString\&}{operatorp[]}{\param{size\_t }{nIndex}}
74
75 Return the array element at position {\it nIndex}. An assert failure will
76 result from an attempt to access an element beyond the end of array in debug
77 mode, but no check is done in release mode.
78
79 This is the operator version of \helpref{Item}{wxarraystringitem} method.
80
81 \membersection{wxArrayString::Add}\label{wxarraystringadd}
82
83 \func{void}{Add}{\param{const wxString\& }{str}}
84
85 Appends a new item to the array.
86
87 See also: \helpref{Insert}{wxarraystringinsert}
88
89 \membersection{wxArrayString::Alloc}\label{wxarraystringalloc}
90
91 \func{void}{Alloc}{\param{size\_t }{nCount}}
92
93 Preallocates enough memory to store {\it nCount} items. This function may be
94 used to improve array class performance before adding a known number of items
95 consecutively.
96
97 See also: \helpref{Dynamic array memory management}{wxarraymemorymanagement}
98
99 \membersection{wxArrayString::Clear}\label{wxarraystringclear}
100
101 \func{void}{Clear}{\void}
102
103 Clears the array contents and frees memory.
104
105 See also: \helpref{Empty}{wxarraystringempty}
106
107 \membersection{wxArrayString::Count}\label{wxarraystringcount}
108
109 \constfunc{size\_t}{Count}{\void}
110
111 Returns the number of items in the array. This function is deprecated and is
112 for backwards compatibility only, please use
113 \helpref{GetCount}{wxarraystringgetcount} instead.
114
115 \membersection{wxArrayString::Empty}\label{wxarraystringempty}
116
117 \func{void}{Empty}{\void}
118
119 Empties the array: after a call to this function
120 \helpref{GetCount}{wxarraystringgetcount} will return $0$. However, this
121 function does not free the memory used by the array and so should be used when
122 the array is going to be reused for storing other strings. Otherwise, you
123 should use \helpref{Clear}{wxarraystringclear} to empty the array and free
124 memory.
125
126 \membersection{wxArrayString::GetCount}\label{wxarraystringgetcount}
127
128 \constfunc{size\_t}{GetCount}{\void}
129
130 Returns the number of items in the array.
131
132 \membersection{wxArrayString::Index}\label{wxarraystringindex}
133
134 \func{int}{Index}{\param{const char *}{ sz}, \param{bool}{ bCase = TRUE}, \param{bool}{ bFromEnd = FALSE}}
135
136 Search the element in the array, starting from the beginning if
137 {\it bFromEnd} is FALSE or from end otherwise. If {\it bCase}, comparison is
138 case sensitive (default), otherwise the case is ignored.
139
140 Returns index of the first item matched or wxNOT\_FOUND if there is no match.
141
142 \membersection{wxArrayString::Insert}\label{wxarraystringinsert}
143
144 \func{void}{Insert}{\param{const wxString\& }{str}, \param{size\_t}{ nIndex}}
145
146 Insert a new element in the array before the position {\it nIndex}. Thus, for
147 example, to insert the string in the beginning of the array you would write
148
149 \begin{verbatim}
150 Insert("foo", 0);
151 \end{verbatim}
152
153 If {\it nIndex} is equal to {\it GetCount() + 1} this function behaves as
154 \helpref{Add}{wxarraystringadd}.
155
156 \membersection{wxArrayString::IsEmpty}\label{wxarraystringisempty}
157
158 \func{}{IsEmpty}{}
159
160 Returns TRUE if the array is empty, FALSE otherwise. This function returns the
161 same result as {\it GetCount() == 0} but is probably easier to read.
162
163 \membersection{wxArrayString::Item}\label{wxarraystringitem}
164
165 \constfunc{wxString\&}{Item}{\param{size\_t }{nIndex}}
166
167 Return the array element at position {\it nIndex}. An assert failure will
168 result from an attempt to access an element beyond the end of array in debug
169 mode, but no check is done in release mode.
170
171 See also \helpref{operator[]}{wxarraystringoperatorindex} for the operator
172 version.
173
174 \membersection{wxArrayString::Last}\label{wxarraystringlast}
175
176 \func{}{Last}{}
177
178 Returns the last element of the array. Attempt to access the last element of
179 an empty array will result in assert failure in debug build, however no checks
180 are done in release mode.
181
182 \membersection{wxArrayString::Remove (by value)}\label{wxarraystringremoveval}
183
184 \func{void}{Remove}{\param{const char *}{ sz}}
185
186 Removes the first item matching this value. An assert failure is provoked by
187 an attempt to remove an element which does not exist in debug build.
188
189 See also: \helpref{Index}{wxarraystringindex}, \helpref{Remove}{wxarraystringremove}
190
191 \membersection{wxArrayString::Remove (by index)}\label{wxarraystringremove}
192
193 \func{void}{Remove}{\param{size\_t }{nIndex}}
194
195 Removes the item at given position.
196
197 See also: \helpref{Remove}{wxarraystringremoveval}
198
199 \membersection{wxArrayString::Shrink}\label{wxarraystringshrink}
200
201 \func{void}{Shrink}{\void}
202
203 Releases the extra memory allocated by the array. This function is useful to
204 minimize the array memory consumption.
205
206 See also: \helpref{Alloc}{wxarraystringalloc}, \helpref{Dynamic array memory management}{wxarraymemorymanagement}
207
208 \membersection{wxArrayString::Sort (alphabetically)}\label{wxarraystringsort}
209
210 \func{void}{Sort}{\param{bool}{ reverseOrder = FALSE}}
211
212 Sorts the array in alphabetical order or in reverse alphabetical order if
213 {\it reverseOrder} is TRUE.
214
215 See also: \helpref{Sort}{wxarraystringsortcallback}
216
217 \membersection{wxArrayString::Sort (user defined)}\label{wxarraystringsortcallback}
218
219 \func{void}{Sort}{\param{CompareFunction }{compareFunction}}
220
221 Sorts the array using the specified {\it compareFunction} for item comparison.
222 {\it CompareFunction} is defined as a function taking two {\it const
223 wxString\&} parameters and returning {\it int} value less than, equal to or
224 greater than 0 if the first string is less than, equal to or greater than the
225 second one.
226
227 Example: sorting strings by their length:
228
229 \begin{verbatim}
230
231 static int CompareStringLen(const wxString& first, const wxString& second)
232 {
233 return first.length() - second.length();
234 }
235
236 ...
237
238 wxArrayString array;
239
240 array.Add("one");
241 array.Add("two");
242 array.Add("three");
243 array.Add("four");
244
245 array.Sort(CompareStringLen);
246
247 \end{verbatim}
248
249 See also: \helpref{Sort}{wxarraystringsort}