QT字符编码转换，可用于中文内码传输

串口、TCP、UDP传输中文字符时，先将字符串转内码。客户端接收到数据后，将内码转为字符串就ＯＫ了

QByteArray CommonFunction::strToInterCode(constQString &str)//字符串转内码

    QString strName = str.toLocal8Bit();

    QByteArray code;

    code.append (strName);

    while(code.count()<8)

        code.append (QByteArray::fromHex ("20"));

    qDebug ()<<"string to intercode"<<QObject::tr("%1").arg (code.toHex ().data ());

    return code;

//内码转字符串,要求为双字节数

QString CommonFunction::interCodeToStr(const QByteArray &data)

    QString str;

    QByteArray temp;

    for(int i= 0;i<data.length();i+=2)

        if(!(data[i] == 0x20 && data[i+1] == 0x20))

            temp.append (data[i]);

            temp.append (data[i+1]);

    str = QString::fromLocal8Bit(temp);

    qDebug ()<< "intercode To string :"<<str;

    return str;

// 字符串转Unicode码

QByteArray CommonFunction::strToUniCode(const QString &str)

    // 这里传来的字符串一定要加tr，main函数里可以加 QTextCodec::setCodecForTr(QTextCodec::codecForLocale());

    QString stt = QObject::tr("%1").arg (str);

    QByteArray data;

    const QChar *q;

    QChar qtmp;

    int num;

    q=stt.unicode();

    int len=stt.count();

    for(int i=0;i<len;i++)

        qtmp =(QChar)*q++;

        num= qtmp.unicode();

        quint8 hi = (quint8)(num >> 8);

        quint8 lo = (quint8)(num);

        data.append (hi);

        data.append (lo);

    while(data.count () <8)

        data.append (QByteArray::fromHex ("20"));

    qDebug ()<<"string to unicode :"<<QObject::tr("%1").arg (data.toHex ().data ());

    return data;

//Unicode码转字符串

QString CommonFunction::uniCodeToStr(const QByteArray &data)

    QByteArray data_1;

    for(int i= 0;i<data.length ();i+=2)

        if(!(data[i] == 0x20 && data[i+1] == 0x20))

            data_1.append (data[i]);

            data_1.append (data[i+1]);

    QString str = data_1.toHex ().data ();

    int temp[400];

    QChar qchar[100];

    QString strOut;

    bool ok;

    int count=str.count();

    int len=count/4;

    for(int i=0;i<count;i+=4)

        temp[i]=str.mid(i,4).toInt(&ok,16);//每四位转化为16进制整型

        qchar[i/4]=temp[i];

        QString str0(qchar, len);

        strOut=str0;

    qDebug ()<<"unicode to string:"<<strOut;

    return strOut;

http://blog.csdn.net/liuguangzhou123/article/details/7478088