QDataStream

Inheritance diagram of QDataStream

Synopsis

Functions

Detailed Description

The PySide.QtCore.QDataStream class provides serialization of binary data to a PySide.QtCore.QIODevice .

A data stream is a binary stream of encoded information which is 100% independent of the host computer’s operating system, CPU or byte order. For example, a data stream that is written by a PC under Windows can be read by a Sun SPARC running Solaris.

You can also use a data stream to read/write raw unencoded binary data . If you want a “parsing” input stream, see PySide.QtCore.QTextStream .

The PySide.QtCore.QDataStream class implements the serialization of C++’s basic data types, like char , short , int , char * , etc. Serialization of more complex data is accomplished by breaking up the data into primitive units.

A data stream cooperates closely with a PySide.QtCore.QIODevice . A PySide.QtCore.QIODevice represents an input/output medium one can read data from and write data to. The PySide.QtCore.QFile class is an example of an I/O device.

Example (write binary data to a stream):

file_ = QFile("file.dat")
file_.open(QIODevice.WriteOnly)
# we will serialize the data into the file
out = QDataStream(file_)
# serialize a string
out.writeQString("the answer is")
# serialize an integer
out.writeInt32(42)

Example (read binary data from a stream):

file_ = QFile("file.dat")
file_.open(QIODevice.ReadOnly)
# read the data serialized from the file
i = QDataStream(file_)
string = ''
a = 0
# extract "the answer is" and 42
string = i.readQString()
a = i.readInt32()

Each item written to the stream is written in a predefined binary format that varies depending on the item’s type. Supported Qt types include PySide.QtGui.QBrush , PySide.QtGui.QColor , PySide.QtCore.QDateTime , PySide.QtGui.QFont , PySide.QtGui.QPixmap , PySide.QtCore.QString , PySide.QtCore.QVariant and many others. For the complete list of all Qt types supporting data streaming see Serializing Qt Data Types .

For integers it is best to always cast to a Qt integer type for writing, and to read back into the same Qt integer type. This ensures that you get integers of the size you want and insulates you from compiler and platform differences.

To take one example, a char * string is written as a 32-bit integer equal to the length of the string including the ‘0’ byte, followed by all the characters of the string including the ‘0’ byte. When reading a char * string, 4 bytes are read to create the 32-bit length value, then that many characters for the char * string including the ‘0’ terminator are read.

The initial I/O device is usually set in the constructor, but can be changed with PySide.QtCore.QDataStream.setDevice() . If you’ve reached the end of the data (or if there is no I/O device set) PySide.QtCore.QDataStream.atEnd() will return true.

Versioning

PySide.QtCore.QDataStream ‘s binary format has evolved since Qt 1.0, and is likely to continue evolving to reflect changes done in Qt. When inputting or outputting complex types, it’s very important to make sure that the same version of the stream ( PySide.QtCore.QDataStream.version() ) is used for reading and writing. If you need both forward and backward compatibility, you can hardcode the version number in the application:

stream.setVersion(QDataStream.Qt_4_0)

If you are producing a new binary data format, such as a file format for documents created by your application, you could use a PySide.QtCore.QDataStream to write the data in a portable format. Typically, you would write a brief header containing a magic string and a version number to give yourself room for future expansion. For example:

file_ = QFile("file.xxx")
file_.open(QIODevice.WriteOnly)
out = QDataStream(file_)

# Write a header with a "magic number" and a version
out.writeInt32(0xA0B0C0D0)
out.writeInt32(123)

out.setVersion(QDataStream.Qt_4_0)

// Write the data
out << lots_of_interesting_data

Then read it in with:

file_ = QFile("file.xxx")
file_.open(QIODevice.ReadOnly)
i = QDataStream(file_)

// Read and check the header
magic = i.readInt32()
if magic != 0xA0B0C0D0:
    return XXX_BAD_FILE_FORMAT

// Read the version
version = i.readInt32()
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

You can select which byte order to use when serializing data. The default setting is big endian (MSB first). Changing it to little endian breaks the portability (unless the reader also changes to little endian). We recommend keeping this setting unless you have special requirements.

Reading and writing raw binary data

You may wish to read/write your own raw binary data to/from the data stream directly. Data may be read from the stream into a preallocated char * using PySide.QtCore.QDataStream.readRawData() . Similarly data can be written to the stream using PySide.QtCore.QDataStream.writeRawData() . Note that any encoding/decoding of the data must be done by you.

A similar pair of functions is PySide.QtCore.QDataStream.readBytes() and PySide.QtCore.QDataStream.writeBytes() . These differ from their raw counterparts as follows: PySide.QtCore.QDataStream.readBytes() reads a quint32 which is taken to be the length of the data to be read, then that number of bytes is read into the preallocated char * ; PySide.QtCore.QDataStream.writeBytes() writes a quint32 containing the length of the data, followed by the data. Note that any encoding/decoding of the data (apart from the length quint32) must be done by you.

Reading and writing Qt collection classes

The Qt container classes can also be serialized to a PySide.QtCore.QDataStream . These include QList , QLinkedList , QVector , QSet , QHash , and QMap . The stream operators are declared as non-members of the classes.

Reading and writing other Qt classes.

In addition to the overloaded stream operators documented here, any Qt classes that you might want to serialize to a PySide.QtCore.QDataStream will have appropriate stream operators declared as non-member of the class:

QDataStream &operator<<(QDataStream &, const QXxx &);
QDataStream &operator>>(QDataStream &, QXxx &);

For example, here are the stream operators declared as non-members of the PySide.QtGui.QImage class:

QDataStream & operator<< (QDataStream& stream, const QImage& image);
QDataStream & operator>> (QDataStream& stream, QImage& image);

To see if your favorite Qt class has similar stream operators defined, check the Related Non-Members section of the class’s documentation page.

See also

PySide.QtCore.QTextStream PySide.QtCore.QVariant

class PySide.QtCore.QDataStream
class PySide.QtCore.QDataStream(arg__1, flags)
class PySide.QtCore.QDataStream(arg__1)
class PySide.QtCore.QDataStream(arg__1)
Parameters:

Constructs a data stream that has no I/O device.

Constructs a data stream that uses the I/O device d .

Warning

If you use QSocket or QSocketDevice as the I/O device d for reading data, you must make sure that enough data is available on the socket for the operation to successfully proceed; PySide.QtCore.QDataStream does not have any means to handle or recover from short-reads.

Constructs a read-only data stream that operates on byte array a . Use PySide.QtCore.QDataStream ( PySide.QtCore.QByteArray *, int) if you want to write to a byte array.

Since PySide.QtCore.QByteArray is not a PySide.QtCore.QIODevice subclass, internally a PySide.QtCore.QBuffer is created to wrap the byte array.

PySide.QtCore.QDataStream.ByteOrder

The byte order used for reading/writing the data.

Constant Description
QDataStream.BigEndian Most significant byte first (the default)
QDataStream.LittleEndian Least significant byte first
PySide.QtCore.QDataStream.FloatingPointPrecision

The precision of floating point numbers used for reading/writing the data. This will only have an effect if the version of the data stream is Qt_4_6 or higher.

Warning

The floating point precision must be set to the same value on the object that writes and the object that reads the data stream.

Constant Description
QDataStream.SinglePrecision All floating point numbers in the data stream have 32-bit precision.
QDataStream.DoublePrecision All floating point numbers in the data stream have 64-bit precision.

Note

This enum was introduced or modified in Qt 4.6

PySide.QtCore.QDataStream.Version

This enum provides symbolic synonyms for the data serialization format version numbers.

Constant Description
QDataStream.Qt_1_0 Version 1 (Qt 1.x)
QDataStream.Qt_2_0 Version 2 (Qt 2.0)
QDataStream.Qt_2_1 Version 3 (Qt 2.1, 2.2, 2.3)
QDataStream.Qt_3_0 Version 4 (Qt 3.0)
QDataStream.Qt_3_1 Version 5 (Qt 3.1, 3.2)
QDataStream.Qt_3_3 Version 6 (Qt 3.3)
QDataStream.Qt_4_0 Version 7 (Qt 4.0, Qt 4.1)
QDataStream.Qt_4_1 Version 7 (Qt 4.0, Qt 4.1)
QDataStream.Qt_4_2 Version 8 (Qt 4.2)
QDataStream.Qt_4_3 Version 9 (Qt 4.3)
QDataStream.Qt_4_4 Version 10 (Qt 4.4)
QDataStream.Qt_4_5 Version 11 (Qt 4.5)
QDataStream.Qt_4_6 Version 12 (Qt 4.6)
QDataStream.Qt_4_7 Same as Qt_4_6 .
PySide.QtCore.QDataStream.Status

This enum describes the current status of the data stream.

Constant Description
QDataStream.Ok The data stream is operating normally.
QDataStream.ReadPastEnd The data stream has read past the end of the data in the underlying device.
QDataStream.ReadCorruptData The data stream has read corrupt data.
PySide.QtCore.QDataStream.atEnd()
Return type:PySide.QtCore.bool

Returns true if the I/O device has reached the end position (end of the stream or file) or if there is no I/O device set; otherwise returns false.

PySide.QtCore.QDataStream.byteOrder()
Return type:PySide.QtCore.QDataStream.ByteOrder

Returns the current byte order setting – either BigEndian or LittleEndian .

PySide.QtCore.QDataStream.device()
Return type:PySide.QtCore.QIODevice

Returns the I/O device currently set, or 0 if no device is currently set.

PySide.QtCore.QDataStream.floatingPointPrecision()
Return type:PySide.QtCore.QDataStream.FloatingPointPrecision

Returns the floating point precision of the data stream.

See also

QDataStream.FloatingPointPrecision PySide.QtCore.QDataStream.setFloatingPointPrecision()

PySide.QtCore.QDataStream.__lshift__(item)
Parameters:itemPySide.QtGui.QTableWidgetItem
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QTextFormat
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(item)
Parameters:itemPySide.QtGui.QStandardItem
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QTime
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(item)
Parameters:itemPySide.QtGui.QTreeWidgetItem
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QUrl
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QTransform
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtScript.QScriptContextInfo
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QRectF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(regExp)
Parameters:regExpPySide.QtCore.QRegExp
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QSizePolicy
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QRegion
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QSize
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QSizeF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QUuid
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(history)
Parameters:historyPySide.QtWebKit.QWebHistory
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QVector2D
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QVector3D
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QVector4D
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QRect
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QTextLength
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QEasingCurve
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QFont
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QLine
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtNetwork.QHostAddress
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QImage
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(ks)
Parameters:ksPySide.QtGui.QKeySequence
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QIcon
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QDateTime
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__1)
Parameters:arg__1 – unicode
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QDate
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QBitArray
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QBrush
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(cursor)
Parameters:cursorPySide.QtGui.QCursor
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QByteArray
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QColor
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QQuaternion
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QPicture
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QPixmap
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QPen
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QPoint
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(polygon)
Parameters:polygonPySide.QtGui.QPolygon
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(array)
Parameters:arrayPySide.QtGui.QPolygonF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QPointF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QLineF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(item)
Parameters:itemPySide.QtGui.QListWidgetItem
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtCore.QLocale
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QMatrix
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(p)
Parameters:pPySide.QtGui.QPalette
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QMatrix4x4
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtNetwork.QNetworkCacheMetaData
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__lshift__(arg__2)
Parameters:arg__2PySide.QtGui.QPainterPath
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QTextLength
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QTime
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QTransform
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QUrl
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QTextFormat
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QUuid
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(item)
Parameters:itemPySide.QtGui.QTreeWidgetItem
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(item)
Parameters:itemPySide.QtGui.QStandardItem
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QRegion
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtScript.QScriptContextInfo
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(item)
Parameters:itemPySide.QtGui.QTableWidgetItem
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QSize
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QSizePolicy
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QVector2D
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QSizeF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QVector4D
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QVector3D
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(regExp)
Parameters:regExpPySide.QtCore.QRegExp
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(history)
Parameters:historyPySide.QtWebKit.QWebHistory
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QMatrix
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QFont
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtNetwork.QHostAddress
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QLineF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QIcon
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(ks)
Parameters:ksPySide.QtGui.QKeySequence
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QLine
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QImage
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QEasingCurve
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QBitArray
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QBrush
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QDateTime
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QByteArray
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(cursor)
Parameters:cursorPySide.QtGui.QCursor
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QDate
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QColor
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QRectF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QPoint
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QPointF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QPixmap
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(polygon)
Parameters:polygonPySide.QtGui.QPolygon
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QQuaternion
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QRect
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(array)
Parameters:arrayPySide.QtGui.QPolygonF
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(item)
Parameters:itemPySide.QtGui.QListWidgetItem
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtCore.QLocale
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QMatrix4x4
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtNetwork.QNetworkCacheMetaData
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QPicture
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QPen
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(arg__2)
Parameters:arg__2PySide.QtGui.QPainterPath
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.__rshift__(p)
Parameters:pPySide.QtGui.QPalette
Return type:PySide.QtCore.QDataStream
PySide.QtCore.QDataStream.readBool()
Return type:PySide.QtCore.bool
PySide.QtCore.QDataStream.readDouble()
Return type:PySide.QtCore.qreal
PySide.QtCore.QDataStream.readFloat()
Return type:PySide.QtCore.float
PySide.QtCore.QDataStream.readInt16()
Return type:PySide.QtCore.qint16
PySide.QtCore.QDataStream.readInt32()
Return type:PySide.QtCore.qint32
PySide.QtCore.QDataStream.readInt64()
Return type:PySide.QtCore.qint64
PySide.QtCore.QDataStream.readInt8()
Return type:PySide.QtCore.qint8
PySide.QtCore.QDataStream.readQChar()
Return type:PySide.QtCore.QChar
PySide.QtCore.QDataStream.readQString()
Return type:unicode
PySide.QtCore.QDataStream.readQStringList()
Return type:list of strings
PySide.QtCore.QDataStream.readQVariant()
Return type:object
PySide.QtCore.QDataStream.readRawData(len)
Parameters:lenPySide.QtCore.int
Return type:PySide.QtCore.int

Reads at most len bytes from the stream into s and returns the number of bytes read. If an error occurs, this function returns -1.

The buffer s must be preallocated. The data is not encoded.

See also

PySide.QtCore.QDataStream.readBytes() QIODevice.read() PySide.QtCore.QDataStream.writeRawData()

PySide.QtCore.QDataStream.readString()
Return type:unicode
PySide.QtCore.QDataStream.readUInt16()
Return type:PySide.QtCore.quint16
PySide.QtCore.QDataStream.readUInt32()
Return type:PySide.QtCore.quint32
PySide.QtCore.QDataStream.readUInt64()
Return type:PySide.QtCore.quint64
PySide.QtCore.QDataStream.readUInt8()
Return type:PySide.QtCore.quint8
PySide.QtCore.QDataStream.resetStatus()

Resets the status of the data stream.

PySide.QtCore.QDataStream.setByteOrder(arg__1)
Parameters:arg__1PySide.QtCore.QDataStream.ByteOrder

Sets the serialization byte order to bo .

The bo parameter can be QDataStream.BigEndian or QDataStream.LittleEndian .

The default setting is big endian. We recommend leaving this setting unless you have special requirements.

PySide.QtCore.QDataStream.setDevice(arg__1)
Parameters:arg__1PySide.QtCore.QIODevice

void QDataStream::setDevice( PySide.QtCore.QIODevice *d)

Sets the I/O device to d , which can be 0 to unset to current I/O device.

PySide.QtCore.QDataStream.setFloatingPointPrecision(precision)
Parameters:precisionPySide.QtCore.QDataStream.FloatingPointPrecision

Sets the floating point precision of the data stream to precision . If the floating point precision is DoublePrecision and the version of the data stream is Qt_4_6 or higher, all floating point numbers will be written and read with 64-bit precision. If the floating point precision is SinglePrecision and the version is Qt_4_6 or higher, all floating point numbers will be written and read with 32-bit precision.

For versions prior to Qt_4_6 , the precision of floating point numbers in the data stream depends on the stream operator called.

The default is DoublePrecision .

Warning

This property must be set to the same value on the object that writes and the object that reads the data stream.

PySide.QtCore.QDataStream.setStatus(status)
Parameters:statusPySide.QtCore.QDataStream.Status

Sets the status of the data stream to the status given.

PySide.QtCore.QDataStream.setVersion(arg__1)
Parameters:arg__1PySide.QtCore.int

Sets the version number of the data serialization format to v .

You don’t have to set a version if you are using the current version of Qt, but for your own custom binary formats we recommend that you do; see Versioning in the Detailed Description.

To accommodate new functionality, the datastream serialization format of some Qt classes has changed in some versions of Qt. If you want to read data that was created by an earlier version of Qt, or write data that can be read by a program that was compiled with an earlier version of Qt, use this function to modify the serialization format used by PySide.QtCore.QDataStream .

Qt Version PySide.QtCore.QDataStream Version
Qt 4.6 12
Qt 4.5 11
Qt 4.4 10
Qt 4.3 9
Qt 4.2 8
Qt 4.0, 4.1 7
Qt 3.3 6
Qt 3.1, 3.2 5
Qt 3.0 4
Qt 2.1, 2.2, 2.3 3
Qt 2.0 2
Qt 1.x 1

The QDataStream.Version enum provides symbolic constants for the different versions of Qt. For example:

out = QDataStream(file_)
out.setVersion(QDataStream.Qt_4_0)

See also

PySide.QtCore.QDataStream.version() QDataStream.Version

PySide.QtCore.QDataStream.skipRawData(len)
Parameters:lenPySide.QtCore.int
Return type:PySide.QtCore.int

Skips len bytes from the device. Returns the number of bytes actually skipped, or -1 on error.

This is equivalent to calling PySide.QtCore.QDataStream.readRawData() on a buffer of length len and ignoring the buffer.

See also

QIODevice.seek()

PySide.QtCore.QDataStream.status()
Return type:PySide.QtCore.QDataStream.Status

Returns the status of the data stream.

PySide.QtCore.QDataStream.unsetDevice()

Unsets the I/O device. Use setDevice(0) instead.

PySide.QtCore.QDataStream.version()
Return type:PySide.QtCore.int

Returns the version number of the data serialization format.

See also

PySide.QtCore.QDataStream.setVersion() QDataStream.Version

PySide.QtCore.QDataStream.writeBool(arg__1)
Parameters:arg__1PySide.QtCore.bool
PySide.QtCore.QDataStream.writeDouble(arg__1)
Parameters:arg__1PySide.QtCore.qreal
PySide.QtCore.QDataStream.writeFloat(arg__1)
Parameters:arg__1PySide.QtCore.float
PySide.QtCore.QDataStream.writeInt16(arg__1)
Parameters:arg__1PySide.QtCore.qint16
PySide.QtCore.QDataStream.writeInt32(arg__1)
Parameters:arg__1PySide.QtCore.qint32
PySide.QtCore.QDataStream.writeInt64(arg__1)
Parameters:arg__1PySide.QtCore.qint64
PySide.QtCore.QDataStream.writeInt8(arg__1)
Parameters:arg__1PySide.QtCore.qint8
PySide.QtCore.QDataStream.writeQChar(arg__1)
Parameters:arg__1PySide.QtCore.QChar
PySide.QtCore.QDataStream.writeQString(arg__1)
Parameters:arg__1 – unicode
PySide.QtCore.QDataStream.writeQStringList(arg__1)
Parameters:arg__1 – list of strings
PySide.QtCore.QDataStream.writeQVariant(arg__1)
Parameters:arg__1 – object
PySide.QtCore.QDataStream.writeRawData(arg__1)
Parameters:arg__1 – str
Return type:PySide.QtCore.int

Writes len bytes from s to the stream. Returns the number of bytes actually written, or -1 on error. The data is not encoded.

See also

PySide.QtCore.QDataStream.writeBytes() QIODevice.write() PySide.QtCore.QDataStream.readRawData()

PySide.QtCore.QDataStream.writeString(arg__1)
Parameters:arg__1 – unicode
PySide.QtCore.QDataStream.writeUInt16(arg__1)
Parameters:arg__1PySide.QtCore.quint16
PySide.QtCore.QDataStream.writeUInt32(arg__1)
Parameters:arg__1PySide.QtCore.quint32
PySide.QtCore.QDataStream.writeUInt64(arg__1)
Parameters:arg__1PySide.QtCore.quint64
PySide.QtCore.QDataStream.writeUInt8(arg__1)
Parameters:arg__1PySide.QtCore.quint8