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void wrapInFunction()
{
//! [0]
QFile file("file.dat");
file.open(QIODevice::WriteOnly);
QDataStream out(&file); // we will serialize the data into the file
out << "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]
}
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