QT #include <QByteArray>定义字节数组

举例说明：QByteArray ba("Hello");存取字符串
QByteArray ba;
ba.resize(5);定义数组大小
ba[0] = 0x3c;
ba[1] = 0xb8;
ba[2] = 0x64;
ba[3] = 0x18;
ba[4] = 0xca;

for (int i = 0; i < ba.size(); ++i)
{
//用ba.at()读取值
if (ba.at(i) >= 'a' && ba.at(i) <= 'f')
cout << "Found character in range [a-f]" << endl;
}