写一个基于 qt c++ 的can dbc解析程序

好的，以下是一个基于 Qt C++ 的 CAN DBC 解析程序的示例代码：

#include <QtCore/QCoreApplication>
#include <QtCore/QDebug>
#include <QtCore/QFile>
#include <QtCore/QTextStream>

struct CANSignal {
    QString name;
    int bitPos;
    int bitLen;
    double factor;
    double offset;
    double min;
    double max;
};

struct CANMessage {
    int id;
    QString name;
    QList<CANSignal> signals;
};

class DBCParser {
public:
    DBCParser(const QString &fileName) {
        QFile file(fileName);
        if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
            qDebug() << "Failed to open file" << fileName;
            return;
        }

        QTextStream in(&file);
        while (!in.atEnd()) {
            QString line = in.readLine().trimmed();
            if (line.startsWith("BO_")) {
                QString idStr = line.section(' ', 1, 1);
                QString name = line.section(' ', 2, 2);
                int id = idStr.toInt();
                messages[id] = {id, name, {}};
            } else if (line.startsWith("SG_")) {
                QString name = line.section(' ', 1, 1);
                QString bitPosStr = line.section(' ', 2, 2);
                QString bitLenStr = line.section(' ', 3, 3);
                QString factorStr = line.section(' ', 4, 4);
                QString offsetStr = line.section(' ', 5, 5);
                QString minStr = line.section(' ', 6, 6);
                QString maxStr = line.section(' ', 7, 7);
                int bitPos = bitPosStr.toInt();
                int bitLen = bitLenStr.toInt();
                double factor = factorStr.toDouble();
                double offset = offsetStr.toDouble();
                double min = minStr.toDouble();
                double max = maxStr.toDouble();
                CANSignal signal = {name, bitPos, bitLen, factor, offset, min, max};

                QString idStr = line.section(' ', 8, 8);
                idStr.remove('(');
                idStr.remove(')');
                int id = idStr.toInt();
                messages[id].signals.append(signal);
            }
        }
    }

    QMap<int, CANMessage> messages;
};

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    DBCParser parser("example.dbc");
    for (int key : parser.messages.keys()) {
        CANMessage message = parser.messages[key];
        qDebug() << "ID:" << message.id << "Name:" << message.name;

        for (CANSignal signal : message.signals) {
            qDebug() << "Signal:" << signal.name << "BitPos:" << signal.bitPos << "BitLen:" << signal.bitLen;
            qDebug() << "Factor:" << signal.factor << "Offset:" << signal.offset << "Min:" << signal.min << "Max:" << signal.max;
        }
    }

    return a.exec();
}

这个程序会读取一个名为 `example.dbc` 的文件，解析其中的 CAN 信号和帧，并将其打印出来。解析过程使用了一个 `DBCParser` 类，该类会读取文件内容，提取出其中的信号和帧数据，并将其保存到 `messages` 映射表中。每个帧都是一个 `CANMessage` 结构体，其中包含 ID、名称和信号列表。每个信号都是一个 `CANSignal` 结构体，其中包含名称、位位置、位长度、因子、偏移量、最小值和最大值。