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1 | \section{wxConfig classes overview}\label{wxconfigoverview} | |
2 | ||
3 | Classes: \helpref{wxConfig}{wxconfigbase} | |
4 | ||
5 | This overview briefly describes what the config classes are and what they are | |
6 | for. All the details about how to use them may be found in the description of | |
7 | the \helpref{wxConfigBase}{wxconfigbase} class and the documentation of the | |
8 | file, registry and INI file based implementations mentions all the | |
9 | features/limitations specific to each one of these versions. | |
10 | ||
11 | The config classes provide a way to store some application configuration | |
12 | information. They were especially designed for this usage and, although may | |
13 | probably be used for many other things as well, should be limited to it. It | |
14 | means that this information should be: | |
15 | ||
16 | \begin{enumerate}\itemsep=0pt | |
17 | \item Typed, i.e. strings or numbers for the moment. You can not store | |
18 | binary data, for example. | |
19 | \item Small. For instance, it is not recommended to use the Windows | |
20 | registry for amounts of data more than a couple of kilobytes. | |
21 | \item Not performance critical, neither from speed nor from a memory | |
22 | consumption point of view. | |
23 | \end{enumerate} | |
24 | ||
25 | On the other hand, the features provided make them very useful for storing all | |
26 | kinds of small to medium volumes of hierarchically-organized, heterogeneous | |
27 | data. In short, this is a place where you can conveniently stuff all your data | |
28 | (numbers and strings) organizing it in a tree where you use the | |
29 | filesystem-like paths to specify the location of a piece of data. In | |
30 | particular, these classes were designed to be as easy to use as possible. | |
31 | ||
32 | From another point of view, they provide an interface which hides the | |
33 | differences between the Windows registry and the standard Unix text format | |
34 | configuration files. Other (future) implementations of wxConfigBase might also | |
35 | understand GTK resource files or their analogues on the KDE side. | |
36 | ||
37 | In any case, each implementation of wxConfigBase does its best to | |
38 | make the data look the same way everywhere. Due to limitations of the underlying | |
39 | physical storage, it may not implement 100\% of the base class functionality. | |
40 | ||
41 | There are groups of entries and the entries themselves. Each entry contains either a string or a number | |
42 | (or a boolean value; support for other types of data such as dates or | |
43 | timestamps is planned) and is identified by the full path to it: something | |
44 | like /MyApp/UserPreferences/Colors/Foreground. The previous elements in the | |
45 | path are the group names, and each name may contain an arbitrary number of entries | |
46 | and subgroups. The path components are {\bf always} separated with a slash, | |
47 | even though some implementations use the backslash internally. Further | |
48 | details (including how to read/write these entries) may be found in | |
49 | the documentation for \helpref{wxConfigBase}{wxconfigbase}. | |
50 |