Qt中的QBitArray类似于C++ STL中的bitset，是专门对存储bit数据而优化设计的容器。典型的应用：将IP地址范围映射为QBitArray，然后就可以以O(1)的效率判断访问IP地址是否匹配某个范围。

The QBitArray class provides an array of bits.

A QBitArray is an array that gives access to individual bits and provides operators (AND, OR, XOR, and NOT) that work on entire arrays of bits. It uses implicit sharing (copy-on-write) to reduce memory usage and to avoid the needless copying of data.

示例代码：

#include <QCoreApplication>
#include <QtCore>

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    auto bitary=QBitArray(10);
    bitary.fill(true);
    bitary.resize(15);
    qDebug() << bitary;
    for(int i=0;i<bitary.size();i++){
        qDebug() << bitary.at(i);
        if(i % 2 ==0){
            bitary.toggleBit(i);
        }
    }

    auto zeroary=QBitArray(bitary);
    zeroary.fill(false);
    qDebug() << bitary;
    qDebug() << zeroary;
    auto orary=bitary^zeroary;
    qDebug() << orary;
    return a.exec();
}

参考资料：

http://qt-project.org/doc/qt-5/QBitArray.html

http://www.cplusplus.com/reference/bitset/bitset/