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The QBitArray class provides an array of bits. More...
#include <qbitarray.h>
Inherits QByteArray.
QString inherits QByteArray, which is defined as QArray<char>.
Since QBitArray is a QArray, it uses explicit sharing with a reference count.
A QBitArray is a special byte array that can access individual bits and perform bit-operations (AND, OR, XOR and NOT) on entire arrays or bits.
Bits can be manipulated by the setBit() and clearBit() functions, but it is also possible to use the indexing [] operator to test and set individual bits. The [] operator is a little slower than the others, because some tricks are required to implement single-bit assignments.
Example:
QBitArray a(3);
a.setBit( 0 );
a.clearBit( 1 );
a.setBit( 2 ); // a = [1 0 1]
QBitArray b(3);
b[0] = 1;
b[1] = 1;
b[2] = 0; // b = [1 1 0]
QBitArray c;
c = ~a & b; // c = [0 1 0]
Constructs an empty bit array.
Constructs a shallow copy of a.
Constructs a bit array of size bits. The bits are uninitialized.
Returns the value (0 or 1) of the bit at position index.
See also operator[]().
Clears the bit at position index (sets it to 0).
See also setBit() and toggleBit().
Returns a deep copy of the bit array.
See also detach().
[virtual protected]Deletes data specific to QBitArray that extended what QGArray provided.
Reimplemented from QGArray.
[virtual]Detaches from shared bit array data and makes sure that this bit array is the only one referring the data.
If multiple bit arrays share common data, this bit array dereferences the data and gets a copy of the data. Nothing will be done if there is just a single reference.
See also copy().
Reimplemented from QGArray.
Fills the bit array with v (1's if v is TRUE, or 0's if v is FALSE).
Will resize the bit array to size bits if size is nonnegative.
Returns FALSE if a nonnegative size was specified and if the bit array could not be resized, otherwise returns TRUE.
See also resize().
Performs the AND operation between all bits in this bit array and a. Returns a reference to this bit array.
The result has the length of the longest bit array of the two, with the bits missing from the shortest array taken as 0.
Example:
QBitArray a( 3 ), b( 2 );
a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1]
b[0] = 1; b[1] = 0; // b = [1 0]
a &= b; // a = [1 0 0]
See also operator|=(), operator^=() and operator~().
Assigns a shallow copy of a to this bit array and returns a reference to this array.
Implements the [] operator for bit arrays.
The returned QBitVal is a context object. It makes it possible to get and set a single bit value.
Example:
QBitArray a( 3 );
a[0] = 0;
a[1] = 1;
a[2] = a[0] ^ a[1];
The functions testBit(), setBit() and clearBit() are faster.
See also at().
Implements the [] operator for constant bit arrays.
Performs the XOR operation between all bits in this bit array and a. Returns a reference to this bit array.
The result has the length of the longest bit array of the two, with the bits missing from the shortest array taken as 0.
Example:
QBitArray a( 3 ), b( 2 );
a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1]
b[0] = 1; b[1] = 0; // b = [1 0]
a ^= b; // a = [0 0 1]
See also operator&=(), operator|=() and operator~().
Performs the OR operation between all bits in this bit array and a. Returns a reference to this bit array.
The result has the length of the longest bit array of the two, with the bits missing from the shortest array taken as 0.
Example:
QBitArray a( 3 ), b( 2 );
a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1]
b[0] = 1; b[1] = 0; // b = [1 0]
a |= b; // a = [1 0 1]
See also operator&=(), operator^=() and operator~().
Returns a bit array which contains the inverted bits of this bit array.
Example:
QBitArray a( 3 ), b;
a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1]
b = ~a; // b = [0 1 0]
Resizes the bit array to size bits. Returns TRUE if the bit array could be resized.
When expanding the bit array, the new bits will be uninitialized.
See also size().
Sets the bit at position index (sets it to 1).
See also clearBit() and toggleBit().
Sets the bit at position index to value.
Equivalent to:
if ( value )
setBit( index );
else
clearBit( index );
See also clearBit() and toggleBit().
Returns the size (number of bits) of the bit array.
See also resize().
Returns TRUE if the bit at position index is set.
See also setBit() and clearBit().
Toggles the bit at position index.
If the previous value was 0, the new value will be 1. If the previous value was 1, the new value will be 0.
See also setBit() and clearBit().
Returns the XOR result between the bit arrays a1 and a2.
See also QBitArray::operator^().
Returns the AND result between the bit arrays a1 and a2.
See also QBitArray::operator&=().
Writes a bit array to a stream.
See also Format of the QDataStream operators
Returns the OR result between the bit arrays a1 and a2.
See also QBitArray::operator|=().
Reads a bit array from a stream.
See also Format of the QDataStream operators
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