diff options
Diffstat (limited to 'src/corelib/doc/snippets/code/src_corelib_io_qdatastream.cpp')
-rw-r--r-- | src/corelib/doc/snippets/code/src_corelib_io_qdatastream.cpp | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/src/corelib/doc/snippets/code/src_corelib_io_qdatastream.cpp b/src/corelib/doc/snippets/code/src_corelib_io_qdatastream.cpp new file mode 100644 index 0000000000..af2d7d24bf --- /dev/null +++ b/src/corelib/doc/snippets/code/src_corelib_io_qdatastream.cpp @@ -0,0 +1,121 @@ +/**************************************************************************** +** +** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). +** Contact: http://www.qt-project.org/ +** +** This file is part of the documentation of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:BSD$ +** You may use this file under the terms of the BSD license as follows: +** +** "Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions are +** met: +** * Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** * Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in +** the documentation and/or other materials provided with the +** distribution. +** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor +** the names of its contributors may be used to endorse or promote +** products derived from this software without specific prior written +** permission. +** +** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +void wrapInFunction() +{ + +//! [0] +QFile file("file.dat"); +file.open(QIODevice::WriteOnly); +QDataStream out(&file); // we will serialize the data into the file +out << QString("the answer is"); // serialize a string +out << (qint32)42; // serialize an integer +//! [0] + + +//! [1] +QFile file("file.dat"); +file.open(QIODevice::ReadOnly); +QDataStream in(&file); // read the data serialized from the file +QString str; +qint32 a; +in >> str >> a; // extract "the answer is" and 42 +//! [1] + + +//! [2] +stream.setVersion(QDataStream::Qt_4_0); +//! [2] + + +//! [3] +QFile file("file.xxx"); +file.open(QIODevice::WriteOnly); +QDataStream out(&file); + +// Write a header with a "magic number" and a version +out << (quint32)0xA0B0C0D0; +out << (qint32)123; + +out.setVersion(QDataStream::Qt_4_0); + +// Write the data +out << lots_of_interesting_data; +//! [3] + + +//! [4] +QFile file("file.xxx"); +file.open(QIODevice::ReadOnly); +QDataStream in(&file); + +// Read and check the header +quint32 magic; +in >> magic; +if (magic != 0xA0B0C0D0) + return XXX_BAD_FILE_FORMAT; + +// Read the version +qint32 version; +in >> version; +if (version < 100) + return XXX_BAD_FILE_TOO_OLD; +if (version > 123) + return XXX_BAD_FILE_TOO_NEW; + +if (version <= 110) + in.setVersion(QDataStream::Qt_3_2); +else + in.setVersion(QDataStream::Qt_4_0); + +// Read the data +in >> lots_of_interesting_data; +if (version >= 120) + in >> data_new_in_XXX_version_1_2; +in >> other_interesting_data; +//! [4] + + +//! [5] +QDataStream out(file); +out.setVersion(QDataStream::Qt_4_0); +//! [5] + +} |