Game Programming using Qt 5 Beginner's Guide - Second Edition

Time for action – Implementing a JSON parser

Let's extend the PlayerInfoJSON class and equip it with a playerInfoFromJson() method:

PlayerInfo PlayerInfoJson::playerInfoFromJson(const QByteArray &ba) {
    QJsonDocument doc = QJsonDocument::fromJson(ba);
    if(!doc.isArray()) {
        return PlayerInfo();
    }
    QJsonArray array = doc.array();
    PlayerInfo pinfo;
    for(const QJsonValue &value: array) {
        pinfo.players << playerFromJson(value.toObject());
    }
    return pinfo;
}

First, we read the document and check whether it is valid and holds the expected array. Upon failure, an empty structure is returned; otherwise, we iterate over the received array and convert each of its elements to an object. Similar to the serialization example, we create a helper function for ...