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The QBitArray class provides an array of bits. More...
All the functions in this class are reentrant when Qt is built with thread support.
#include <qbitarray.h>
Inherits QByteArray.
Because QBitArray is a QMemArray, it uses explicit sharing with a reference count.
A QBitArray is a special byte array that can access individual bits and perform bitoperations (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 setBit() and clearBit() because some tricks are required to implement singlebit 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]
When a QBitArray is constructed the bits are uninitialized. Use fill() to set all the bits to 0 or 1. The array can be resized with resize() and copied with copy(). Bits can be set with setBit() and cleared with clearBit(). Bits can be toggled with toggleBit(). A bit's value can be obtained with testBit() and with at().
QBitArray supports the & (AND),  (OR), ^ (XOR) and ~ (NOT) operators.
See also Collection Classes, Implicitly and Explicitly Shared Classes, and NonGUI Classes.
See also fill().
Constructs a shallow copy of a.
Returns the value (0 or 1) of the bit at position index.
See also operator[]().
See also setBit() and toggleBit().
See also detach().
If multiple bit arrays share common data, this bit array dereferences the data and gets a copy of the data. Nothing happens if there is only a single reference.
See also copy().
Reimplemented from QMemArray.
fill() resizes the bit array to size bits if size is nonnegative.
Returns FALSE if a nonnegative size was specified and the bit array could not be resized; otherwise returns TRUE.
See also resize().
The result has the length of the longest of the two bit arrays, with any missing bits (i.e. if one array is shorter than the other), taken to be 0.
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 by its index position.
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.
The result has the length of the longest of the two bit arrays, with any missing bits (i.e. if one array is shorter than the other), taken to be 0.
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~().
The result has the length of the longest of the two bit arrays, with any missing bits (i.e. if one array is shorter than the other), taken to be 0.
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~().
Example:
QBitArray a( 3 ), b; a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1] b = ~a; // b = [0 1 0]
If the array is expanded, the new bits are set to 0.
See also size().
Sets the bit at position index to value.
Equivalent to:
if ( value ) setBit( index ); else clearBit( index );
See also clearBit() and toggleBit().
Sets the bit at position index to 1.
See also clearBit() and toggleBit().
Returns the bit array's size (number of bits).
See also resize().
See also setBit() and clearBit().
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 AND result between the bit arrays a1 and a2.
The result has the length of the longest of the two bit arrays, with any missing bits (i.e. if one array is shorter than the other), taken to be 0.
See also QBitArray::operator&=().
Writes bit array a to stream s.
See also Format of the QDataStream operators.
Reads a bit array into a from stream s.
See also Format of the QDataStream operators.
Returns the XOR result between the bit arrays a1 and a2.
The result has the length of the longest of the two bit arrays, with any missing bits (i.e. if one array is shorter than the other), taken to be 0.
See also QBitArray::operator^().
Returns the OR result between the bit arrays a1 and a2.
The result has the length of the longest of the two bit arrays, with any missing bits (i.e. if one array is shorter than the other), taken to be 0.
See also QBitArray::operator=().
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