QBuffer

 #include <QBuffer>

     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'

     QByteArray byteArray;
     QBuffer buffer(&byteArray);
     buffer.open(QIODevice::WriteOnly);

     QDataStream out(&buffer);
     out << QApplication::palette();

     QPalette palette;
     QBuffer buffer(&byteArray);
     buffer.open(QIODevice::ReadOnly);

     QDataStream in(&buffer);
     in >> palette;

Member Function Documentation

QBuffer::QBuffer ( QObject * parent = 0 )

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().

QBuffer::QBuffer ( QByteArray * byteArray, QObject * parent = 0 )

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().

QBuffer::~QBuffer ()

Destroys the buffer.

bool QBuffer::atEnd () const [virtual]

Reimplemented from QIODevice::atEnd().

QByteArray & QBuffer::buffer ()

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

See also setBuffer() and data().

const QByteArray & QBuffer::buffer () const

This is an overloaded function.

This is the same as data().

bool QBuffer::canReadLine () const [virtual]

Reimplemented from QIODevice::canReadLine().

void QBuffer::close () [virtual]

Reimplemented from QIODevice::close().

const QByteArray & QBuffer::data () const

Returns the data contained in the buffer.

This is the same as buffer().

See also setData() and setBuffer().

bool QBuffer::open ( OpenMode flags ) [virtual]

Reimplemented from QIODevice::open().

qint64 QBuffer::pos () const [virtual]

Reimplemented from QIODevice::pos().

qint64 QBuffer::readData ( char * data, qint64 len ) [virtual protected]

Reimplemented from QIODevice::readData().

bool QBuffer::seek ( qint64 pos ) [virtual]

Reimplemented from QIODevice::seek().

void QBuffer::setBuffer ( QByteArray * byteArray )

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.

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

void QBuffer::setData ( const QByteArray & data )

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.

See also data() and setBuffer().

void QBuffer::setData ( const char * data, int size )

This is an overloaded function.

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

qint64 QBuffer::size () const [virtual]

Reimplemented from QIODevice::size().

qint64 QBuffer::writeData ( const char * data, qint64 len ) [virtual protected]

Reimplemented from QIODevice::writeData().