这里给出封装的两个函数，用于将结构体st_subject和Json之间进行相互转化：

#include <QJsonObject>
#include <QJsonArray>
#include <QJsonValue>
#include <QJsonDocument>
// 将st_subject结构体转换为Json
QJsonObject st_subjectToJson(const st_subject& subject) {
    QJsonObject json;
    json["subject_number"] = subject.subject_number;
    json["subject_type"] = subject.subject_type;
    json["subject_name"] = subject.subject_name;
    // 图片信息转换为Base64字符串存储
    QByteArray imageData;
    QBuffer buffer(&imageData);
    buffer.open(QIODevice::WriteOnly);
    subject.image.save(&buffer, "PNG");  // 假设图片格式为PNG
    QString base64Image = QString::fromLatin1(imageData.toBase64().data());
    json["image"] = base64Image;
    // 根据题目类型存储对应的答案信息
    switch (subject.subject_type) {
        case 0: {  // True or False
            QJsonObject trueFalseAnswerObj;
            trueFalseAnswerObj["banswer"] = subject.subject_Type.trueOrfalse.banswer;
            trueFalseAnswerObj["banswer_standard"] = subject.subject_Type.trueOrfalse.banswer_standard;
            trueFalseAnswerObj["bret"] = subject.subject_Type.trueOrfalse.bret;
            json["subject_Type"] = trueFalseAnswerObj;
            break;
        }
        case 1: {  // Choose
            QJsonObject chooseAnswerObj;
            chooseAnswerObj["banswer"] = subject.subject_Type.choose.banswer;
            chooseAnswerObj["banswer_standard"] = subject.subject_Type.choose.banswer_standard;
            chooseAnswerObj["bret"] = subject.subject_Type.choose.bret;
            json["subject_Type"] = chooseAnswerObj;
            break;
        }
        case 2: {  // Choose Multiple
            QJsonObject chooseMultipleAnswerObj;
            QJsonArray banswerArray, banswerStandardArray;
            for (int i : subject.subject_Type.choose_multiple.banswer) {
                banswerArray.append(i);
            }
            for (int i : subject.subject_Type.choose_multiple.banswer_standard) {
                banswerStandardArray.append(i);
            }
            chooseMultipleAnswerObj["banswer"] = banswerArray;
            chooseMultipleAnswerObj["banswer_standard"] = banswerStandardArray;
            chooseMultipleAnswerObj["bret"] = subject.subject_Type.choose_multiple.bret;
            json["subject_Type"] = chooseMultipleAnswerObj;
            
			break;
        }
    }
    return json;
}
// 将Json转换为st_subject结构体
st_subject jsonToSt_subject(const QJsonObject& json) {
    st_subject subject;
    subject.subject_number = json["subject_number"].toInt();
    subject.subject_type = json["subject_type"].toInt();
    subject.subject_name = json["subject_name"].toString();
    // 从Base64字符串还原图片信息
    QString base64Image = json["image"].toString();
    QByteArray imageData = QByteArray::fromBase64(base64Image.toLatin1());
    QImage image;
    image.loadFromData(imageData);  // 假设图片格式为PNG
    subject.image = image;
    // 根据题目类型提取对应的答案信息
    switch (subject.subject_type) {
        case 0: {  // True or False
            QJsonObject trueFalseAnswerObj = json["subject_Type"].toObject();
            
			subject.subject_Type.trueOrfalse.banswer =
                trueFalseAnswerObj["banswer"].toBool();
            subject.subject_Type.trueOrfalse.banswer_standard =
                trueFalseAnswerObj["banswer_standard"].toBool();
            subject.subject_Type.trueOrfalse.bret = 
				trueFalseAnswerObj["bret"].toBool();
            
			break;
        }
        case 1: {  // Choose
            QJsonObject chooseAnswerObj = json["subject_Type"].toObject();
            subject.subject_Type.choose.banswer =
                chooseAnswerObj["banswer"].toInt();
            subject.subject_Type.choose.banswer_standard =
                chooseAnswerObj["banswer_standard"].toInt();
            subject.subject_Type.choose.bret = 
				chooseAnswerObj["bret"].toBool();
            break;
        }
        case 2: {  // Choose Multiple
            QJsonObject chooseMultipleAnswerObj = json["subject_Type"].toObject();
            QJsonArray banswerArray = chooseMultipleAnswerObj["banswer"].toArray();
            for (const QJsonValue& value : banswerArray) {
                subject.subject_Type.choose_multiple.banswer.append(value.toInt());
            }
            QJsonArray banswerStandardArray = chooseMultipleAnswerObj["banswer_standard"].toArray();
            for (const QJsonValue& value : banswerStandardArray) {
                subject.subject_Type.choose_multiple.banswer_standard.append(value.toInt());
            }
            subject.subject_Type.choose_multiple.bret =
                chooseMultipleAnswerObj["bret"].toBool();
             break;
        }
    }
    return subject;
}

这样就可以使用这两个函数来进行结构体st_subject和Json之间的相互转化了。希望对你有帮助！


内容由零声教学AI助手提供，问题来源于学员提问