Qt编写地图实现省市区域图的示例代码

QStringList EchartJs::getInfoFromData(const QByteArray &data)
{
    //取出对应的城市名称和经纬度
    //以下两种方法测试过解析时间,json大概1S,字符串分割大概5S,json方法更快
    QStringList result;
#if (QT_VERSioN > QT_VERSION_CHECK(5,0,0))
    //采用qt内置的json方法解析
    QJsonParseError error;
    QJsonDocument jsonDoc = QJsonDocument::fromJson(data, &error);
    if (error.error == QJsonParseError::NoError) {
        QJsonObject rootObj = jsonDoc.object();
        //qDebug() << rootObj.keys();

        if (rootObj.contains("features")) {
            QJsonArray features = rootObj.value("features").toArray();
            for (int i = 0; i < features.count(); i++) {
                QJsonValue value = features.at(i);
                QJsonObject subObj = value.toObject();
                if (subObj.contains("properties")) {
                    QJsonObject nodeObj = subObj.value("properties").toObject();
                    QStringList list;
                    QJsonArray array = nodeObj.value("cp").toArray();
                    for (int k = 0; k < array.count(); k++) {
                        list << QString::number(array.at(k).toDouble());
                    }

                    QString name = nodeObj.value("name").toString();
                    QString cp = list.join(",");
                    result << QString("%1|%2").arg(name).arg(cp);
                }
            }
        }
    }
#else
    //采用字符串分割方法解析
    QString temp = data;
    temp = temp.mid(0, temp.length() - 24);
    QString flag = "properties";
    int len = temp.length();
    for (int i = 0; i < len; i++) {
        QString str = temp.mid(i, 10);
        if (str == flag) {
            str = temp.mid(i, 100);
            str = str.mid(13, str.indexOf("},") - 13);
            str = str.replace("}", "");
            //到这步数据已经变成 "cp":[121.490317,31.222771],"name":"黄浦区","childNum":1
            //cp name的顺序可能不一样,所以需要分割字符串重新判断
            QString name, cp;
            QStringList list = str.split(",");
            foreach (QString s, list) {
                if (s.startsWith("\"cp\"")) {
                    cp = s.mid(6, s.length());
                } else if (s.startsWith("\"name\"")) {
                    name = s.mid(8, s.length());
                    name = name.replace("\"", "");
                } else if (s.startsWith("\"childNum\"")) {

                } else {
                    //经纬度会拆分成两部分,一部分在这里 31.222771]
                    cp = QString("%1,%2").arg(cp).arg(s.left(s.length() - 1));
                }
            }

            result << QString("%1|%2").arg(name).arg(cp);
        }
    }
#endif
    return result;
}