如何从QDataStream读取数组

时间:2017-06-28 14:28:35

标签: c++ qt

我想将存储在矢量(保存结构)中的数据写入文件,并从该文件中读取数据。我尝试用QDataStream执行此操作并重载">>"和"<<&#;运营商。一切都工作,直到我添加一个char数组到结构。 我尝试从QDataStream中读取字符串的方式一定有问题。我尝试了不同的方法来读取字符串,但我总是收到错误。

以下是结构:

typedef struct
{
   char data[cNetworkMessageLengthMax + 1];   //cNetworkMessageLengthMax=19
} __attribute__((packed)) networkMessageBody_t;


typedef struct 
{
    baseStation_daytime_t   timestamp;
    uint32_t                blueId;
    networkMessageBody_t    message;
} __attribute__((packed)) baseStation_mailbox_t;

和运营商:

QDataStream &operator<<(QDataStream &out, const std::vector<baseStation_mailbox_t> &data)
{
    for(uint8_t i=0; i < data.size(); i++)
    {
        out << data[i].timestamp.time.hour;
        out << data[i].timestamp.time.minute;
        out << data[i].timestamp.time.second;
        out << data[i].timestamp.time.thousandth;
        out << data[i].timestamp.date.day;
        out << data[i].timestamp.date.month;
        out << data[i].timestamp.date.year;

        out << data[i].blueId;

        out << data[i].message.data;
    }
    return out;
}

QDataStream &operator>>(QDataStream &in, std::vector<baseStation_mailbox_t> &data)
{
    uint16_t tmp16;
    uint32_t tmp32;
    char tmpChar[20];

    uint8_t i = 0;
    while(in.atEnd() == false)
    {
        data.emplace_back();

        in >> data[i].timestamp.time.hour;
        in >> data[i].timestamp.time.minute;
        in >> data[i].timestamp.time.second;
        in >> tmp16;
        data[i].timestamp.time.thousandth = tmp16;
        in >> data[i].timestamp.date.day;
        in >> data[i].timestamp.date.month;
        in >> tmp16;
        data[i].timestamp.date.year = tmp16;

        in >> tmp32;
        data[i].blueId = tmp32;

        in >> tmpChar;                 //HERE I get errors
        data[i].message.data = tmpChar;

        i++;
    }

    return in;
    }

1 个答案:

答案 0 :(得分:2)

取代:

  • out << data[i].message.data;out << QByteArray::fromRawData(data[i].message.data,std::extent<decltyple(data[i].message.data)>::value);
  • char tmpChar[20];QByteArray tmpChar;
  • data[i].message.data = tmpChar;std::copy(tmpChar.constBegin(),tempChar.constEnd(),data[i].message.data);