I/O device which operates on temporary files. More...

Inheritance diagram for QTemporaryFile:

Public Methods
	QTemporaryFile ()

	QTemporaryFile (const QString &fileName)

	QTemporaryFile (const QString &fileName, QObject *parent)

	QTemporaryFile (QObject *parent)

	~QTemporaryFile ()

bool	autoRemove () const

QString	fileName () const override

QString	fileTemplate () const

bool	open ()

void	setAutoRemove (bool b)

void	setFileTemplate (const QString &fileName)

Public Methods inherited from QFile
	QFile ()

	QFile (const QString &name)

	QFile (const QString &name, QObject *parent)

	QFile (QObject *parent)

	~QFile ()

bool	copy (const QString &newName)

bool	exists () const

bool	link (const QString &newName)

bool	open (FILE *fHandle, OpenMode mode, FileHandleFlags handleFlags=DontCloseHandle)

bool	open (int fd, OpenMode mode, FileHandleFlags handleFlags=DontCloseHandle)

QFileDevice::Permissions	permissions () const override

QString	readLink () const

bool	remove ()

bool	rename (const QString &newName)

bool	resize (qint64 sz) override

void	setFileName (const QString &name)

bool	setPermissions (QFileDevice::Permissions permissions) override

qint64	size () const override

QString	symLinkTarget () const

Public Methods inherited from QFileDevice
	~QFileDevice ()

bool	atEnd () const override

void	close () override

FileError	error () const

QDateTime	fileTime (QFileDevice::FileTimeType type) const

bool	flush ()

int	handle () const

bool	isSequential () const override

uchar *	map (qint64 offset, qint64 size, MemoryMapFlags flags=NoOptions)

qint64	pos () const override

bool	seek (qint64 pos) override

bool	setFileTime (const QDateTime &newTime, QFileDevice::FileTimeType type)

qint64	size () const override

bool	unmap (uchar *address)

void	unsetError ()

Public Methods inherited from QIODevice
	QIODevice ()

	QIODevice (QObject *parent)

virtual	~QIODevice ()

virtual qint64	bytesAvailable () const

virtual qint64	bytesToWrite () const

virtual bool	canReadLine () const

QString	errorString () const

bool	getChar (char *c)

bool	isOpen () const

bool	isReadable () const

bool	isTextModeEnabled () const

bool	isWritable () const

OpenMode	openMode () const

qint64	peek (char *data, qint64 maxSize)

QByteArray	peek (qint64 maxSize)

bool	putChar (char c)

qint64	read (char *data, qint64 maxSize)

QByteArray	read (qint64 maxSize)

QByteArray	readAll ()

qint64	readLine (char *data, qint64 maxSize)

QByteArray	readLine (qint64 maxSize=0)

virtual bool	reset ()

void	setTextModeEnabled (bool enabled)

void	ungetChar (char c)

virtual bool	waitForBytesWritten (int msecs)

virtual bool	waitForReadyRead (int msecs)

qint64	write (const char *data)

qint64	write (const char *data, qint64 maxSize)

qint64	write (const QByteArray &data)

Public Methods inherited from QObject
	QObject (QObject *parent=nullptr)

	~QObject ()

bool	blockSignals (bool block)

const QList< QObject * > &	children () const

bool	connect (const QObject *sender, const QString &signalMethod, const QString &location, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)

bool	connect (const QObject *sender, const QString &signalMethod, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)

bool	disconnect (const QObject *receiver, const QString &slotMethod=QString ()) const

bool	disconnect (const QString &signalMethod, const QString &location, const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const

bool	disconnect (const QString &signalMethod=QString (), const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const

void	dumpObjectInfo ()

void	dumpObjectTree ()

QList< QString >	dynamicPropertyNames () const

virtual bool	event (QEvent *event)

virtual bool	eventFilter (QObject watched, QEvent event)

template<typename T >
T	findChild (const QString &childName=QString ()) const

template<class T >
QList< T >	findChildren (const QRegularExpression &regExp, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const

template<class T >
QList< T >	findChildren (const QString &childName=QString (), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const

bool	inherits (const QString &className) const

void	installEventFilter (QObject *filterObj)

bool	isWidgetType () const

bool	isWindowType () const

void	killTimer (int id)

const QMetaObject *	metaObject () const

void	moveToThread (QThread *targetThread)

QString	objectName () const

QObject *	parent () const

template<class T = QVariant>
T	property (const QString &name) const

void	removeEventFilter (QObject *obj)

void	setObjectName (const QString &name)

void	setParent (QObject *parent)

bool	setProperty (const QString &name, const QVariant &value)

bool	signalsBlocked () const

int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)

QThread *	thread () const

Static Public Methods
static QTemporaryFile *	createNativeFile (const QString &fileName)

static QTemporaryFile *	createNativeFile (QFile &file)

Static Public Methods inherited from QFile
static bool	copy (const QString &oldName, const QString &newName)

static QString	decodeName (const char *localFileName)

static QString	decodeName (const QByteArray &localFileName)

static QByteArray	encodeName (const QString &fileName)

static bool	exists (const QString &fileName)

static bool	link (const QString &oldName, const QString &newName)

static QFileDevice::Permissions	permissions (const QString &fileName)

static QString	readLink (const QString &fileName)

static bool	remove (const QString &fileName)

static bool	rename (const QString &oldName, const QString &newName)

static bool	resize (const QString &filename, qint64 sz)

static void	setDecodingFunction (DecoderFn function)

static void	setEncodingFunction (EncoderFn function)

static bool	setPermissions (const QString &fileName, QFileDevice::Permissions permissions)

static QString	symLinkTarget (const QString &fileName)

Static Public Methods inherited from QObject
static bool	connect (const QObject sender, const QMetaMethod &signalMethod, const QObject receiver, const QMetaMethod &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)

static bool	connect (const QObject sender, const QString &signalMethod, const QObject receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection, const QString &location=QString ())

static bool	connect (const QObject sender, const QString &signalMethod, const QString &location, const QObject receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)

template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn >
static bool	connect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver receiver, SlotReturn (SlotClass::slotMethod)(SlotArgs...), Qt::ConnectionType type=Qt::AutoConnection)

template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T >
static bool	connect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver *receiver, T slotLambda, Qt::ConnectionType type=Qt::AutoConnection)

static bool	disconnect (const QObject sender, const QMetaMethod &signalMethod, const QObject receiver, const QMetaMethod &slotMethod)

static bool	disconnect (const QObject sender, const QString &signalMethod, const QObject receiver, const QString &slotMethod)

static bool	disconnect (const QObject sender, const QString &signalMethod, const QString &location, const QObject receiver, const QString &slotMethod)

static bool	disconnect (const QObject sender, std::nullptr_t, const QObject receiver, std::nullptr_t)

template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn >
static bool	disconnect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver receiver, SlotReturn (SlotClass::slotMethod)(SlotArgs...))

template<class Sender , class SignalClass , class... SignalArgs, class Receiver >
static bool	disconnect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver *receiver, std::nullptr_t slotMethod=nullptr)

template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T >
static bool	disconnect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver *receiver, T slotMethod)

static QMetaObject &	staticMetaObject ()

static QString	tr (const char text, const char comment=nullptr, std::optional< int > numArg=std::optional< int >())

Protected Methods
bool	open (OpenMode flags) override

Protected Methods inherited from QFileDevice
qint64	readData (char *data, qint64 maxSize) override

qint64	readLineData (char *data, qint64 maxSize) override

qint64	writeData (const char *data, qint64 maxSize) override

Protected Methods inherited from QIODevice
void	setErrorString (const QString &errorString)

void	setOpenMode (OpenMode openMode)

Protected Methods inherited from QObject
virtual void	childEvent (QChildEvent *event)

virtual void	connectNotify (const QMetaMethod &signalMethod) const

virtual void	customEvent (QEvent *event)

virtual void	disconnectNotify (const QMetaMethod &signalMethod) const

bool	isSignalConnected (const QMetaMethod &signalMethod) const

int	receivers (const QString &signal) const

QObject *	sender () const

int	senderSignalIndex () const

virtual void	timerEvent (QTimerEvent *event)

Friends
class	QFile

Additional Inherited Members
Public Typedefs inherited from QFile
using	DecoderFn = QString (*)(const QByteArray &localfileName)

using	EncoderFn = QByteArray (*)(const QString &fileName)

Public Typedefs inherited from QFileDevice
using	FileHandleFlags = QFlags< FileHandleFlag >

using	Permissions = QFlags< Permission >

Public Typedefs inherited from QIODevice
using	OpenMode = QFlags< OpenModeFlag >

Public Types inherited from QFileDevice
enum	FileError

enum	FileHandleFlag

enum	FileTimeType

enum	MemoryMapFlags

enum	Permission

Public Types inherited from QIODevice
enum	OpenModeFlag

Public Signals inherited from QIODevice
void	aboutToClose ()

void	bytesWritten (qint64 bytes)

void	readChannelFinished ()

void	readyRead ()

Public Signals inherited from QObject
void	destroyed (QObject *obj=nullptr)

void	objectNameChanged (const QString &objectName)

Public Slots inherited from QObject
void	deleteLater ()

Properties inherited from QObject
	objectName

Related Functions inherited from QObject
T	qobject_cast (QObject *object)

	QObjectList

Detailed Description

The QTemporaryFile class is an I/O device which operates on temporary files. The class is used to create unique temporary files. The file is not actually created until the open() method is called. The file must be opened before retrieving the file name. By default, the file will be removed when the QTemporaryFile object is destroyed.

The name of the temporary file is guaranteed to be unique and will not overwrite an existing file. The desired file name can be passed to the constructor or one will be auto generated.

QTemporaryFile tmpFile;
 
if (tmpFile.open()) {
   // call fileName() to return the file name
}

Reopening a QTemporaryFile after calling close() is supported, as long as the QTemporaryFile is not destroyed.

A temporary file will have a file name based on the value of QCoreApplication::applicationName() and an auto generated part. If the application name was not set the base file will be cs_temp.

For more information about the auto generated part refer to setFileTemplate().

Constructors

By default, the file is stored in the system temporary directory which can be obtained by calling QDir::tempPath().

If the constructor which accepts a file name is called and no path is provided, the file will be placed in the current working directory. If a path is supplied the file will be located specified directory.

See also: QDir::tempPath(), QFile

Constructor & Destructor Documentation

QTemporaryFile::QTemporaryFile ( )

Constructs a QTemporaryFile based on the template name. When this temporary file is opened the template name will be used to create a unique file name.

The template name is based on the application name, which is returned by calling QCoreApplication::applicationName(). If the application name is empty the template name is defaulted to cs_temp.

The file will be stored in the system's temporary directory. This location can be obtained by calling QDir::tempPath().

See also: open()

QTemporaryFile::QTemporaryFile ( const QString & fileName )

explicit

Constructs a QTemporaryFile based on the given fileName. The name of the temporary file will be generated based on the template name. This name is a combination of a path and a file name. The file name is the portion of the name after the last directory path separator.

If the template name is a relative path, the path will be relative to the current working directory.

If fileName contains "XXXXXX" (six X characters in a row) the X's will be replaced by random letters to create a unique file name. If fileName does not contain "XXXXXX" then six random letters will be appended as the file extension.

See also: open(), setFileTemplate()

QTemporaryFile::QTemporaryFile ( QObject * parent )

explicit

Constructs a QTemporaryFile with the given parent. When the temporary file is opened the template name will be used to create a unique file name.

The template name is based on the application name, which is returned by calling QCoreApplication::applicationName(). If the application name is empty the template name is defaulted to cs_temp.

The file will be stored in the system's temporary directory. This location can be obtained by calling QDir::tempPath().

See also: open(), setFileTemplate()

QTemporaryFile::QTemporaryFile	(	const QString &	fileName,
		QObject *	parent
	)

Constructs a QTemporaryFile with using fileName and parent. When the temporary file is opened the template name will be used to create a unique file name.

See also: open(), setFileTemplate()

QTemporaryFile::~QTemporaryFile ( )

Destroys the temporary file object. The file is automatically closed if necessary and when AutoRemove mode is enabled the file will be deleted.

See also: autoRemove()

Method Documentation

bool QTemporaryFile::autoRemove ( ) const

Returns true if the QTemporaryFile is in AutoRemove mode. AutoRemove mode will automatically delete the file from disk upon destruction.

This makes it very easy to create your QTemporaryFile object on the stack, fill it with data, read from it, and finally on function return it will automatically clean up after itself.

AutoRemove is true by default.

See also: setAutoRemove(), remove()

QTemporaryFile * QTemporaryFile::createNativeFile ( const QString & fileName )

inlinestatic

Opens the existing file specified by fileName. Then calls the other version of createNativeFile() which accepts a QFile.

QTemporaryFile * QTemporaryFile::createNativeFile ( QFile & file )

static

If file is not on a local disk, a temporary file is created on a local disk, file is copied into the temporary local file, and a pointer to the temporary local file is returned. If file is already on a local disk, a copy is not created and nullptr is returned.

QFile f(":/resources/file.txt");
QTemporaryFile::createNativeFile(f);    // Returns a pointer to a temporary file
 
QFile f("/users/fred/file.txt");
QTemporaryFile::createNativeFile(f);    // Returns nullptr

QString QTemporaryFile::fileName ( ) const

overridevirtual

Returns the complete file name. The return value will be empty before the open() method is called.

See also: fileTemplate()

Reimplemented from QFile::fileName()

QString QTemporaryFile::fileTemplate ( ) const

Returns the current template file name.

See also: setFileTemplate()

bool QTemporaryFile::open ( )

inline

A QTemporaryFile is opened in QIODevice::ReadWrite mode which allows reading and writing to the given file. This method will return true upon success. Once the file is open, calling the method fileName() will return the unique temporary file name.

See also: fileName()

bool QTemporaryFile::open ( OpenMode flags )

overrideprotectedvirtual

Creates a unique file name for this QTemporaryFile and opens it using the given flags. The unique file name is obtained by calling fileName(). The file is guaranteed to be a new file.

Since this overloaded method is protected, it can only called from an inherited class.

Reimplemented from QFile::open()

void QTemporaryFile::setAutoRemove ( bool b )

Sets the QTemporaryFile to AutoRemove mode if b is true. AutoRemove is true by default.

See also: autoRemove(), remove()

void QTemporaryFile::setFileTemplate ( const QString & fileName )

Sets the internal template name to fileName. The name of the temporary file will be generated based on the template name. This name is a combination of a path and a file name. The file name is the portion of the name after the last directory path separator.

If the template name is a relative path, the path will be relative to the current working directory.

If fileName contains "XXXXXX" (six X characters in a row) the X's will be replaced by random letters to create a unique file name. If fileName does not contain "XXXXXX" then six random letters will be appended as the file extension.

To create a temporary file with no extension, the six X's must be included in the fileName as shown below.

QTemporaryFile tmpFile;
 
tmpFile.setFileTemplate(QDir::tempPath() + "myFileName_XXXXXX");

See also: fileTemplate()

Public Methods

Static Public Methods

Protected Methods

Friends

Additional Inherited Members

Detailed Description

Constructors

Constructor & Destructor Documentation

Method Documentation