QtCore.QBuffer Class Reference

The QBuffer class provides a QIODevice interface for a QByteArray. More...

Inheritance diagram for QtCore.QBuffer:

Collaboration diagram for QtCore.QBuffer:

Public Member Functions
	QBuffer (QObject parent=null)
	QBuffer (QByteArray buf, QObject parent=null)
override void	CreateProxy ()
override bool	AtEnd ()
override bool	CanReadLine ()
override void	Close ()
override bool	Open (QIODevice.OpenModeFlag openMode)
override long	Pos ()
override bool	Seek (long off)
new void	SetData (string data, int len)
override long	Size ()
new void	Dispose ()
Public Member Functions inherited from QtCore.QIODevice
	QIODevice ()
	QIODevice (QObject parent)
override void	CreateProxy ()
virtual long	BytesAvailable ()
virtual long	BytesToWrite ()
new string	ErrorString ()
new bool	GetChar (Pointer< sbyte > c)
new bool	IsOpen ()
new bool	IsReadable ()
virtual bool	IsSequential ()
new bool	IsTextModeEnabled ()
new bool	IsWritable ()
new QIODevice.OpenModeFlag	OpenMode ()
new QByteArray	Peek (long maxlen)
new long	Peek (Pointer< sbyte > data, long maxlen)
new bool	PutChar (sbyte c)
new QByteArray	Read (long maxlen)
new long	Read (Pointer< sbyte > data, long maxlen)
new QByteArray	ReadAll ()
new QByteArray	ReadLine (long maxlen=0)
new long	ReadLine (Pointer< sbyte > data, long maxlen)
virtual bool	Reset ()
new void	SetTextModeEnabled (bool enabled)
new void	UngetChar (sbyte c)
virtual bool	WaitForBytesWritten (int msecs)
virtual bool	WaitForReadyRead (int msecs)
new long	Write (QByteArray data)
new long	Write (string data)
new long	Write (string data, long len)
new void	Dispose ()
Public Member Functions inherited from QtCore.QObject
	QObject (QObject parent=null)
new bool	BlockSignals (bool b)
new System.Collections.Generic.List < QObject >	Children ()
new bool	Connect (QObject sender, string signal, string member, Qt.ConnectionType type=Qt.ConnectionType.AutoConnection)
new void	DeleteLater ()
new bool	Disconnect (QObject receiver, string member=null)
new bool	Disconnect (string signal=null, QObject receiver=null, string member=null)
new void	DumpObjectInfo ()
new void	DumpObjectTree ()
new System.Collections.Generic.List < QByteArray >	DynamicPropertyNames ()
virtual bool	OnEvent (QEvent arg1)
virtual bool	EventFilter (QObject arg1, QEvent arg2)
new bool	Inherits (string classname)
new void	InstallEventFilter (QObject arg1)
new bool	IsWidgetType ()
new void	KillTimer (int id)
new object	Property (string name)
new void	RemoveEventFilter (QObject arg1)
new bool	SetProperty (string name, object value)
new void	SetUserData (uint id, QObjectUserData data)
new bool	SignalsBlocked ()
new int	StartTimer (int interval)
new QObjectUserData	UserData (uint id)
new void	Dispose ()
Public Member Functions inherited from QtCore.Qt
delegate QTextStream	FuncQTextStreamQTextStream (QTextStream qTextStream)
delegate string	FuncStringQByteArray (QByteArray qByteArray)
delegate QByteArray	FuncQByteArrayString (string @string)
delegate void	ActionQtMsgTypeString (QtMsgType qtMsgType, string @string)
delegate QObject	FuncQObject ()

Static Public Member Functions
static string	Tr (string s, string c=null)
static string	Tr (string s, string c, int n)
static string	TrUtf8 (string s, string c=null)
static string	TrUtf8 (string s, string c, int n)
Static Public Member Functions inherited from QtCore.QIODevice
static string	Tr (string s, string c=null)
static string	Tr (string s, string c, int n)
static string	TrUtf8 (string s, string c=null)
static string	TrUtf8 (string s, string c, int n)
Static Public Member Functions inherited from QtCore.QObject
static bool	Connect (QObject sender, QMetaMethod signal, QObject receiver, QMetaMethod method, Qt.ConnectionType type=Qt.ConnectionType.AutoConnection)
static bool	Connect (QObject sender, string signal, QObject receiver, string member, Qt.ConnectionType arg5=Qt.ConnectionType.AutoConnection)
static bool	Disconnect (QObject sender, QMetaMethod signal, QObject receiver, QMetaMethod member)
static bool	Disconnect (QObject sender, string signal, QObject receiver, string member)
static uint	RegisterUserData ()
static string	Tr (string s, string c=null)
static string	Tr (string s, string c, int n)
static string	TrUtf8 (string s, string c=null)
static string	TrUtf8 (string s, string c, int n)
Static Public Member Functions inherited from QtCore.Qt
static QDataStream	Write (QDataStream s, object p)
static QDataStream	Write (QDataStream arg1, QSizeF arg2)
static QTextStream	Write (QTextStream s, Qt.FuncQTextStreamQTextStream f)
static QDataStream	Write (QDataStream arg1, QPoint arg2)
static QDataStream	Write (QDataStream arg1, QLineF arg2)
static QDataStream	Write (QDataStream arg1, QPointF arg2)
static QDataStream	Write (QDataStream arg1, QChar arg2)
static QDataStream	Write (QDataStream arg1, QByteArray arg2)
static QDataStream	Write (QDataStream arg1, QEasingCurve arg2)
static QDataStream	Write (QDataStream arg1, QRectF arg2)
static QDataStream	Write (QDataStream arg1, QDateTime arg2)
static QDataStream	Write (QDataStream arg1, QUrl arg2)
static QDataStream	Write (QDataStream arg1, QTime arg2)
static QDataStream	Write (QDataStream arg1, QLocale arg2)
static QDataStream	Write (QDataStream arg1, QBitArray arg2)
static QDataStream	Write (QDataStream arg1, QUuid arg2)
static QDataStream	Write (QDataStream arg1, QLine arg2)
static QDataStream	Write (QDataStream arg1, QDate arg2)
static QDataStream	Write (QDataStream @out, QRegExp regExp)
static QDataStream	Write (QDataStream arg1, QRect arg2)
static QDataStream	Write (QDataStream arg1, QSize arg2)
static QDataStream	Write (QDataStream s, QVariant.Type p)
static QDataStream	Write (QDataStream arg1, string arg2)
static QDataStream	Write (QDataStream @out, System.Collections.Generic.List< string > list)
static QDataStream	Read (QDataStream arg1, QChar arg2)
static QDataStream	Read (QDataStream arg1, QLocale arg2)
static QDataStream	Read (QDataStream arg1, QRect arg2)
static QDataStream	Read (QDataStream arg1, QEasingCurve arg2)
static QDataStream	Read (QDataStream arg1, QDate arg2)
static QDataStream	Read (QDataStream arg1, QUrl arg2)
static QDataStream	Read (QDataStream arg1, QUuid arg2)
static QTextStream	Read (QTextStream s, Qt.FuncQTextStreamQTextStream f)
static QDataStream	Read (QDataStream arg1, QLineF arg2)
static QDataStream	Read (QDataStream arg1, QRectF arg2)
static QDataStream	Read (QDataStream arg1, QPointF arg2)
static QDataStream	Read (QDataStream arg1, QLine arg2)
static QDataStream	Read (QDataStream arg1, QBitArray arg2)
static QDataStream	Read (QDataStream arg1, QSize arg2)
static QDataStream	Read (QDataStream arg1, QDateTime arg2)
static QDataStream	Read (QDataStream arg1, QTime arg2)
static QDataStream	Read (QDataStream arg1, QPoint arg2)
static QDataStream	Read (QDataStream @in, QRegExp regExp)
static QDataStream	Read (QDataStream s, object p)
static QDataStream	Read (QDataStream arg1, QByteArray arg2)
static QDataStream	Read (QDataStream arg1, QSizeF arg2)
static QDataStream	Read (QDataStream arg1, string arg2)
static QDataStream	Read (QDataStream s, QVariant.Type p)
static QDataStream	Read (QDataStream @in, System.Collections.Generic.List< string > list)
static double	qAcos (double v)
static void	qAddPostRoutine (System.Action arg1)
static string	qAppName ()
static double	qAsin (double v)
static double	qAtan (double v)
static double	qAtan2 (double x, double y)
static void	qBadAlloc ()
static int	qCeil (double v)
static ushort	qChecksum (string s, uint len)
static QByteArray	qCompress (QByteArray data)
static QByteArray	qCompress (QByteArray data, int compressionLevel=-1)
static QByteArray	qCompress (Pointer< byte > data, int nbytes)
static QByteArray	qCompress (Pointer< byte > data, int nbytes, int compressionLevel=-1)
static double	qCos (double v)
static double	qExp (double v)
static double	qFabs (double v)
static double	qFastCos (double x)
static double	qFastSin (double x)
static string	qFlagLocation (string method)
static int	qFloor (double v)
static bool	qFuzzyCompare (double p1, double p2)
static bool	qFuzzyCompare (float p1, float p2)
static bool	qFuzzyIsNull (double d)
static bool	qFuzzyIsNull (float f)
static uint	qHash (QBitArray key)
static uint	qHash (QChar key)
static uint	qHash (QStringRef key)
static uint	qHash (QUrl url)
static uint	qHash (QPersistentModelIndex index)
static uint	qHash (QByteArray key)
static uint	qHash (QModelIndex index)
static uint	qHash (uint key)
static uint	qHash (sbyte key)
static uint	qHash (byte key)
static uint	qHash (short key)
static uint	qHash (NativeLong key)
static uint	qHash (ushort key)
static uint	qHash (long key)
static uint	qHash (ulong key)
static uint	qHash (int key)
static uint	qHash (string key)
static uint	qHash (NativeULong key)
static double	qInf ()
static Qt.ActionQtMsgTypeString	qInstallMsgHandler (Qt.ActionQtMsgTypeString arg1)
static int	qIntCast (float f)
static int	qIntCast (double f)
static bool	qIsFinite (double d)
static bool	qIsFinite (float f)
static bool	qIsInf (float f)
static bool	qIsInf (double d)
static bool	qIsNaN (float f)
static bool	qIsNaN (double d)
static bool	qIsNull (float f)
static bool	qIsNull (double d)
static double	qLn (double v)
static double	qPow (double x, double y)
static double	qQNaN ()
static void	qRegisterStaticPluginInstanceFunction (Qt.FuncQObject function)
static void	qRemovePostRoutine (System.Action arg1)
static int	qRound (double d)
static long	qRound64 (double d)
static double	qSNaN ()
static bool	qSharedBuild ()
static double	qSin (double v)
static double	qSqrt (double v)
static bool	qStringComparisonHelper (QStringRef s1, string s2)
static double	qTan (double v)
static QByteArray	qUncompress (QByteArray data)
static QByteArray	qUncompress (Pointer< byte > data, int nbytes)
static string	qVersion ()
static void	Qbswap_helper (Pointer< byte > src, Pointer< byte > dest, int size)
static QByteArray	Qgetenv (string varName)
static bool	Qputenv (string varName, QByteArray value)
static int	Qrand ()
static void	Qsrand (uint seed)
static int	Qstrcmp (QByteArray str1, QByteArray str2)
static int	Qstrcmp (QByteArray str1, string str2)
static int	Qstrcmp (string str1, QByteArray str2)
static int	Qstrcmp (string str1, string str2)
static Pointer< sbyte >	Qstrcpy (Pointer< sbyte > dst, string src)
static Pointer< sbyte >	Qstrdup (string arg1)
static int	Qstricmp (string arg1, string arg2)
static uint	Qstrlen (string str)
static int	Qstrncmp (string str1, string str2, uint len)
static Pointer< sbyte >	Qstrncpy (Pointer< sbyte > dst, string src, uint len)
static int	Qstrnicmp (string arg1, string arg2, uint len)
static uint	Qstrnlen (string str, uint maxlen)
static string	QtTrId (string id, int n=-1)

Protected Member Functions
	QBuffer (System.Type dummy)
override void	ConnectNotify (string arg1)
override void	DisconnectNotify (string arg1)
override long	ReadData (Pointer< sbyte > data, long maxlen)
override long	WriteData (string data, long len)
Protected Member Functions inherited from QtCore.QIODevice
	QIODevice (System.Type dummy)
new void	OnAboutToClose ()
new void	OnBytesWritten (long bytes)
new void	OnReadChannelFinished ()
virtual long	ReadLineData (Pointer< sbyte > data, long maxlen)
new void	OnReadyRead ()
new void	SetErrorString (string errorString)
new void	SetOpenMode (QIODevice.OpenModeFlag openMode)
Protected Member Functions inherited from QtCore.QObject
	QObject (System.Type dummy)
virtual void	OnChildEvent (QChildEvent arg1)
virtual void	OnCustomEvent (QEvent arg1)
new void	OnDestroyed (QObject arg1=null)
new int	Receivers (string signal)
new QObject	Sender ()
new int	SenderSignalIndex ()
virtual void	OnTimerEvent (QTimerEvent arg1)

Properties
new QByteArray	Buffer [get, set]
new QByteArray	Data [get, set]
static new QMetaObject	StaticMetaObject [get]
new IQBufferSignals	Emit [get]
Properties inherited from QtCore.QIODevice
Slot	ReadyRead
Slot< System.Int64 >	BytesWritten
Slot	AboutToClose
Slot	ReadChannelFinished
static new QMetaObject	StaticMetaObject [get]
new IQIODeviceSignals	Emit [get]
Properties inherited from QtCore.QObject
virtual EventHandler < QEventArgs< QChildEvent > >	ChildEvent
virtual EventHandler < QEventArgs< QEvent > >	CustomEvent
virtual EventHandler < QEventArgs< QEvent > >	Event
virtual EventHandler < QEventArgs< QTimerEvent > >	TimerEvent
Slot< QObject >	DestroyedQObject
Slot	Destroyed
new QObject	Parent [get, set]
virtual System.IntPtr	SmokeObject [get, set]
new string	ObjectName [get, set]
static new QMetaObject	StaticMetaObject [get]
static new QMetaObject	StaticQtMetaObject [get]
new IQObjectSignals	Emit [get]

Additional Inherited Members
Public Types inherited from QtCore.QIODevice
enum	OpenModeFlag {   Append = 4, NotOpen = 0, ReadOnly = 1, ReadWrite = 3,   Text = 16, Truncate = 8, Unbuffered = 32, WriteOnly = 2 }
	More...
Protected Attributes inherited from QtCore.QObject
object	Q_EMIT = null
SmokeInvocation	interceptor
readonly List< QEventHandler >	eventFilters = new List<QEventHandler>()

Detailed Description

The QBuffer class provides a QIODevice interface for a QByteArray.

QBuffer allows you to access a QByteArray using the QIODevice interface. The QByteArray is treated just as a standard random-accessed file. Example:

QBuffer buffer;

char ch;

buffer.open(QBuffer::ReadWrite);

buffer.write("Qt rocks!");

buffer.seek(0);

buffer.getChar(&ch); // ch == 'Q'

buffer.getChar(&ch); // ch == 't'

buffer.getChar(&ch); // ch == ' '

buffer.getChar(&ch); // ch == 'r'

By default, an internal QByteArray buffer is created for you when you create a QBuffer. You can access this buffer directly by calling buffer(). You can also use QBuffer with an existing QByteArray by calling setBuffer(), or by passing your array to QBuffer's constructor.

Call open() to open the buffer. Then call write() or putChar() to write to the buffer, and read(), readLine(), readAll(), or getChar() to read from it. size() returns the current size of the buffer, and you can seek to arbitrary positions in the buffer by calling seek(). When you are done with accessing the buffer, call close().

The following code snippet shows how to write data to a QByteArray using QDataStream and QBuffer:

QByteArray byteArray;

QBuffer buffer(&byteArray);

buffer.open(QIODevice::WriteOnly);

QDataStream out(&buffer);

out << QApplication::palette();

Effectively, we convert the application's QPalette into a byte array. Here's how to read the data from the QByteArray:

QPalette palette;

QBuffer buffer(&byteArray);

buffer.open(QIODevice::ReadOnly);

QDataStream in(&buffer);

in >> palette;

QTextStream and QDataStream also provide convenience constructors that take a QByteArray and that create a QBuffer behind the scenes.

QBuffer emits readyRead() when new data has arrived in the buffer. By connecting to this signal, you can use QBuffer to store temporary data before processing it. For example, you can pass the buffer to QFtp when downloading a file from an FTP server. Whenever a new payload of data has been downloaded, readyRead() is emitted, and you can process the data that just arrived. QBuffer also emits bytesWritten() every time new data has been written to the buffer.

See also QFile, QDataStream, QTextStream, and QByteArray.

Constructor & Destructor Documentation

QtCore.QBuffer.QBuffer ( System.Type  dummy )

protected

QtCore.QBuffer.QBuffer

(

QObject

parent = null

)

Constructs an empty buffer with the given parent. You can call setData() to fill the buffer with data, or you can open it in write mode and use write().

See also open().

QtCore.QBuffer.QBuffer	(	QByteArray	buf,
		QObject	parent = null
	)

Constructs a QBuffer that uses the QByteArray pointed to by byteArray as its internal buffer, and with the given parent. The caller is responsible for ensuring that byteArray remains valid until the QBuffer is destroyed, or until setBuffer() is called to change the buffer. QBuffer doesn't take ownership of the QByteArray.

If you open the buffer in write-only mode or read-write mode and write something into the QBuffer, byteArray will be modified.

Example:

QByteArray byteArray("abc");

QBuffer buffer(&byteArray);

buffer.open(QIODevice::WriteOnly);

buffer.seek(3);

buffer.write("def", 3);

buffer.close();

// byteArray == "abcdef"

See also open(), setBuffer(), and setData().

Member Function Documentation

override bool QtCore.QBuffer.AtEnd ( )

virtual

Reimplemented from QIODevice::atEnd().

Reimplemented from QtCore.QIODevice.

override bool QtCore.QBuffer.CanReadLine ( )

virtual

Reimplemented from QIODevice::canReadLine().

Reimplemented from QtCore.QIODevice.

override void QtCore.QBuffer.Close ( )

virtual

Reimplemented from QIODevice::close().

Reimplemented from QtCore.QIODevice.

override void QtCore.QBuffer.ConnectNotify ( string  signal )

protectedvirtual

This virtual function is called when something has been connected to signal in this object.

If you want to compare signal with a specific signal, use QLatin1String and the SIGNAL() macro as follows:

if (QLatin1String(signal) == SIGNAL(valueChanged(int))) {

// signal is valueChanged(int)

}

If the signal contains multiple parameters or parameters that contain spaces, call QMetaObject::normalizedSignature() on the result of the SIGNAL() macro.

Warning: This function violates the object-oriented principle of modularity. However, it might be useful when you need to perform expensive initialization only if something is connected to a signal.

See also connect() and disconnectNotify().

Reimplemented from QtCore.QObject.

override void QtCore.QBuffer.CreateProxy ( )

virtual

Reimplemented from QtCore.QObject.

override void QtCore.QBuffer.DisconnectNotify ( string  signal )

protectedvirtual

This virtual function is called when something has been disconnected from signal in this object.

See connectNotify() for an example of how to compare signal with a specific signal.

Warning: This function violates the object-oriented principle of modularity. However, it might be useful for optimizing access to expensive resources.

See also disconnect() and connectNotify().

Reimplemented from QtCore.QObject.

new void QtCore.QBuffer.Dispose

(

)

override bool QtCore.QBuffer.Open ( QIODevice.OpenModeFlag  openMode )

virtual

Reimplemented from QIODevice::open().

Reimplemented from QtCore.QIODevice.

override long QtCore.QBuffer.Pos ( )

virtual

Reimplemented from QIODevice::pos().

Reimplemented from QtCore.QIODevice.

override long QtCore.QBuffer.ReadData ( Pointer< sbyte >  data, long  maxlen  )

protectedvirtual

Reimplemented from QIODevice::readData().

Implements QtCore.QIODevice.

override bool QtCore.QBuffer.Seek ( long  off )

virtual

Reimplemented from QIODevice::seek().

Reimplemented from QtCore.QIODevice.

new void QtCore.QBuffer.SetData	(	string	data,
		int	len
	)

This is an overloaded function.

Sets the contents of the internal buffer to be the first size bytes of data.

override long QtCore.QBuffer.Size ( )

virtual

Reimplemented from QIODevice::size().

Reimplemented from QtCore.QIODevice.

static string QtCore.QBuffer.Tr ( string  s, string  c = null  )

static

static string QtCore.QBuffer.Tr ( string  s, string  c, int  n  )

static

static string QtCore.QBuffer.TrUtf8 ( string  s, string  c = null  )

static

static string QtCore.QBuffer.TrUtf8 ( string  s, string  c, int  n  )

static

override long QtCore.QBuffer.WriteData ( string  data, long  len  )

protectedvirtual

Reimplemented from QIODevice::writeData().

Implements QtCore.QIODevice.

Property Documentation

new QByteArray QtCore.QBuffer.Buffer

getset

Returns a reference to the QBuffer's internal buffer. You can use it to modify the QByteArray behind the QBuffer's back.

Makes QBuffer uses the QByteArray pointed to by byteArray as its internal buffer. The caller is responsible for ensuring that byteArray remains valid until the QBuffer is destroyed, or until setBuffer() is called to change the buffer. QBuffer doesn't take ownership of the QByteArray.

Does nothing if isOpen() is true.

If you open the buffer in write-only mode or read-write mode and write something into the QBuffer, byteArray will be modified.

Example:

QByteArray byteArray("abc");

QBuffer buffer;

buffer.setBuffer(&byteArray);

buffer.open(QIODevice::WriteOnly);

buffer.seek(3);

buffer.write("def", 3);

buffer.close();

// byteArray == "abcdef"

If byteArray is 0, the buffer creates its own internal QByteArray to work on. This byte array is initially empty.

new QByteArray QtCore.QBuffer.Data

getset

Returns the data contained in the buffer.

This is the same as buffer().

Sets the contents of the internal buffer to be data. This is the same as assigning data to buffer().

Does nothing if isOpen() is true.

new IQBufferSignals QtCore.QBuffer.Emit

getprotected

new QMetaObject QtCore.QBuffer.StaticMetaObject

staticget