qt json操作

json文件结构形式

{
    "xiao1": [
        {
            "000100": {
                "industryCode": "000100",
                "industryName": "test"
            }
        },
        {
            "000101": {
                "industryCode": "000100",
                "industryName": "test"
            }
        },
        {
            "000103": {
                "industryCode": "000100",
                "industryName": "test"
            }
        }
    ],
    "xiaogdsadg": [
        {
            "12321344": {
                "industryCode": "12321344",
                "industryName": "454555"
            }
        },
        {
            "54545445": {
                "industryCode": "54545445",
                "industryName": "454555"
            }
        },
        {
            "454454654": {
                "industryCode": "454454654",
                "industryName": "454555"
            }
        }
    ]
}

//判断指定项是否在json文件里

bool MainWindow:: isInJson(QString userName,QString rowId)

{

 ???QString val;

 ???QFile file;

 ???file.setFileName("F:\\work\\qtProjects\\untitled11\\test123.json");

 ???file.open(QIODevice::ReadOnly| QIODevice::Text);

 ???val = file.readAll();

 ???file.close();

 ???QJsonDocument doc = QJsonDocument::fromJson(val.toUtf8());

 ???QJsonObject objTop1 = doc.object();

 ???QStringList keys = objTop1.keys();

 ???//用户循环

 ???for(int i = 0; i < keys.count();i++)

 ???{

 ???????if(keys.at(i)!= userName)

 ???????????continue;

 ???????QJsonArray arrayRows = objTop1.value(keys.at(i)).toArray();

 ???????//行循环

 ???????for(int j =0;j < arrayRows.count();j++)

 ???????{

 ???????????QJsonObject objRow = arrayRows.at(j).toObject();

 ???????????if(objRow.keys().at(0) == rowId)

 ???????????{

 ???????????????return true;

 ???????????}

 ???????}

 ???}

 ???return false;

}

//添加收藏

void MainWindow::addJson(QString userName, QString rowId)

{

 ???if(!isInJson(userName,rowId))

 ???{

 ???????bool hasUser = false;

 ???????QString val;

 ???????QFile file;

 ???????file.setFileName("F:\\work\\qtProjects\\untitled11\\test123.json");

 ???????file.open(QIODevice::ReadOnly| QIODevice::Text);

 ???????val = file.readAll();

 ???????file.close();

 ???????QJsonDocument doc = QJsonDocument::fromJson(val.toUtf8());

 ???????QJsonObject objTop1 = doc.object();

 ???????QStringList keys = objTop1.keys();

 ???????//用户循环

 ???????for(int i = 0; i < keys.count();i++)

 ???????{

 ???????????if(keys.at(i) != userName)

 ???????????????continue;

 ???????????QJsonArray arrayRows = objTop1.value(keys.at(i)).toArray();

 ???????????QJsonObject addObj;

 ???????????QJsonObject addObj1;

 ???????????addObj1.insert("industryCode",rowId);

 ???????????addObj1.insert("industryName","454555");

 ???????????addObj.insert(rowId,addObj1);

 ???????????arrayRows.append(addObj);

 ???????????objTop1.insert(userName,arrayRows);

 ???????????hasUser = true;

 ???????????break;

 ???????}

 ???????//该用户还没有添加

 ???????if(!hasUser)

 ???????{

 ???????????QJsonArray arrayRows;

 ???????????QJsonObject addObj;

 ???????????QJsonObject addObj1;

 ???????????addObj1.insert("industryCode",rowId);

 ???????????addObj1.insert("industryName","444545");

 ???????????addObj.insert(rowId,addObj1);

 ???????????arrayRows.append(addObj);

 ???????????objTop1.insert(userName,arrayRows);

 ???????}

 ???????doc.setObject(objTop1);

 ???????file.setFileName("F:\\work\\qtProjects\\untitled11\\test123.json");

 ???????file.open(QIODevice::WriteOnly| QIODevice::Text);

 ???????file.write(doc.toJson());

 ???????file.close();

 ???}

}

//取消收藏

void MainWindow::removeJson(QString userName, QString rowId)

{

 ???if(isInJson(userName,rowId))

 ???{

 ???????QString val;

 ???????QFile file;

 ???????file.setFileName("F:\\work\\qtProjects\\untitled11\\test123.json");

 ???????file.open(QIODevice::ReadOnly| QIODevice::Text);

 ???????val = file.readAll();

 ???????file.close();

 ???????QJsonDocument doc = QJsonDocument::fromJson(val.toUtf8());

 ???????QJsonObject objTop1 = doc.object();

 ???????QStringList keys = objTop1.keys();

 ???????//用户循环

 ???????for(int i = 0; i < keys.count();i++)

 ???????{

 ???????????if(keys.at(i) != userName)

 ???????????????continue;

 ???????????QJsonArray arrayRows = objTop1.value(keys.at(i)).toArray();

 ???????????//行循环

 ???????????for(int j =0;j < arrayRows.count();j++)

 ???????????{

 ???????????????QJsonObject objRow = arrayRows.at(j).toObject();

 ???????????????if(objRow.keys().at(0) == rowId)

 ???????????????{

 ???????????????????arrayRows.removeAt(j);

 ???????????????????objTop1.insert(userName,arrayRows);

 ???????????????????break;

 ???????????????}

 ???????????}

 ???????????doc.setObject(objTop1);

 ???????????file.setFileName("F:\\work\\qtProjects\\untitled11\\test123.json");

 ???????????file.open(QIODevice::WriteOnly| QIODevice::Text);

 ???????????file.write(doc.toJson());

 ???????????file.close();

 ???????????break;

 ???????}

 ???}

}

qt json操作

原文地址：https://www.cnblogs.com/tianmochou/p/9264430.html