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1\section{\class{wxDataInputStream}}\label{wxdatainputstream}
2
3This class provides functions that read binary data types in a
4portable way. Data can be read in either big-endian or little-endian
5format, little-endian being the default on all architectures.
6
7If you want to read data from text files (or streams) use
8\helpref{wxTextInputStream}{wxtextinputstream} instead.
9
10The >> operator is overloaded and you can use this class like a standard C++ iostream.
11Note, however, that the arguments are the fixed size types wxUint32, wxInt32 etc
12and on a typical 32-bit computer, none of these match to the "long" type (wxInt32
13is defined as signed int on 32-bit architectures) so that you cannot use long. To avoid
14problems (here and elsewhere), make use of the wxInt32, wxUint32, etc types.
15
16For example:
17
18\begin{verbatim}
19 wxFileInputStream input( "mytext.dat" );
20 wxDataInputStream store( input );
21 wxUint8 i1;
22 float f2;
23 wxString line;
24
25 store >> i1; // read a 8 bit integer.
26 store >> i1 >> f2; // read a 8 bit integer followed by float.
27 store >> line; // read a text line
28\end{verbatim}
29
30See also \helpref{wxDataOutputStream}{wxdataoutputstream}.
31
32\wxheading{Derived from}
33
34None
35
36\wxheading{Include files}
37
38<wx/datstrm.h>
39
40\latexignore{\rtfignore{\wxheading{Members}}}
41
42\membersection{wxDataInputStream::wxDataInputStream}\label{wxdatainputstreamctor}
43
44\func{}{wxDataInputStream}{\param{wxInputStream\&}{ stream}}
45
46\func{}{wxDataInputStream}{\param{wxInputStream\&}{ stream}, \param{wxMBConv\&}{ conv = wxMBConvUTF8}}
47
48Constructs a datastream object from an input stream. Only read methods will
49be available. The second form is only available in Unicode build of wxWidgets.
50
51\wxheading{Parameters}
52
53\docparam{stream}{The input stream.}
54
55\docparam{conv}{Charset conversion object object used to decode strings in Unicode
56mode (see \helpref{wxDataInputStream::ReadString}{wxdatainputstreamreadstring}
57documentation for detailed description). Note that you must not destroy
58{\it conv} before you destroy this wxDataInputStream instance!}
59
60\membersection{wxDataInputStream::\destruct{wxDataInputStream}}\label{wxdatainputstreamdtor}
61
62\func{}{\destruct{wxDataInputStream}}{\void}
63
64Destroys the wxDataInputStream object.
65
66\membersection{wxDataInputStream::BigEndianOrdered}\label{wxdatainputstreambigendianordered}
67
68\func{void}{BigEndianOrdered}{\param{bool}{ be\_order}}
69
70If {\it be\_order} is true, all data will be read in big-endian
71order, such as written by programs on a big endian architecture
72(e.g. Sparc) or written by Java-Streams (which always use
73big-endian order).
74
75\membersection{wxDataInputStream::Read8}\label{wxdatainputstreamread8}
76
77\func{wxUint8}{Read8}{\void}
78
79Reads a single byte from the stream.
80
81\func{void}{Read8}{\param{wxUint8 *}{buffer}, \param{size\_t }{size}}
82
83Reads bytes from the stream in a specified buffer. The amount of
84bytes to read is specified by the {\it size} variable.
85
86\membersection{wxDataInputStream::Read16}\label{wxdatainputstreamread16}
87
88\func{wxUint16}{Read16}{\void}
89
90Reads a 16 bit unsigned integer from the stream.
91
92\func{void}{Read16}{\param{wxUint16 *}{buffer}, \param{size\_t }{size}}
93
94Reads 16 bit unsigned integers from the stream in a specified buffer. the
95amount of 16 bit unsigned integer to read is specified by the {\it size} variable.
96
97\membersection{wxDataInputStream::Read32}\label{wxdatainputstreamread32}
98
99\func{wxUint32}{Read32}{\void}
100
101Reads a 32 bit unsigned integer from the stream.
102
103\func{void}{Read32}{\param{wxUint32 *}{buffer}, \param{size\_t }{size}}
104
105Reads 32 bit unsigned integers from the stream in a specified buffer. the amount of
10632 bit unsigned integer to read is specified by the {\it size} variable.
107
108\membersection{wxDataInputStream::Read64}\label{wxdatainputstreamread64}
109
110\func{wxUint64}{Read64}{\void}
111
112Reads a 64 bit unsigned integer from the stream.
113
114\func{void}{Read64}{\param{wxUint64 *}{buffer}, \param{size\_t }{size}}
115
116Reads 64 bit unsigned integers from the stream in a specified buffer. the amount of
11764 bit unsigned integer to read is specified by the {\it size} variable.
118
119\membersection{wxDataInputStream::ReadDouble}\label{wxdatainputstreamreaddouble}
120
121\func{double}{ReadDouble}{\void}
122
123Reads a double (IEEE encoded) from the stream.
124
125\func{void}{ReadDouble}{\param{double *}{buffer}, \param{size\_t }{size}}
126
127Reads double data (IEEE encoded) from the stream in a specified buffer. the amount of
128double to read is specified by the {\it size} variable.
129
130\membersection{wxDataInputStream::ReadString}\label{wxdatainputstreamreadstring}
131
132\func{wxString}{ReadString}{\void}
133
134Reads a string from a stream. Actually, this function first reads a long
135integer specifying the length of the string (without the last null character)
136and then reads the string.
137
138In Unicode build of wxWidgets, the fuction first reads multibyte (char*)
139string from the stream and then converts it to Unicode using the {\it conv}
140object passed to constructor and returns the result as wxString. You are
141responsible for using the same convertor as when writing the stream.
142
143See also \helpref{wxDataOutputStream::WriteString}{wxdataoutputstreamwritestring}.
144