QMap容器小知识

QMap<QString, int> map;
...
foreach (int value, map)
    cout << value << endl;

bool contains(const Key &key) const

const T value(const Key &key, const T &defaultValue = T()) const

QVariantMap map;
map["apple"]  = 1;
map.value("orange", 0).toInt();

const T value(const Key &key, const T &defaultValue = T()) const

T &operator[](const Key &key)
const T operator[](const Key &key) const

QMap<Key, T> &QMap::unite(const QMap<Key, T> &other)

QVariantMap map1;
map1["apple"]  = 1;
map1["orange"] = 1;

QVariantMap map2;
map2["orange"] = 1;

map1.unite(map2);

qDebug()<<map1;

QMap(("apple", QVariant(int, 1))("orange", QVariant(int, 1))("orange", QVariant(int, 1)))

T QMap::take(const Key &key)