// Copyright (C) 2016 The Qt Company Ltd. // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause //! [0] QMap map; //! [0] //! [1] map["one"] = 1; map["three"] = 3; map["seven"] = 7; //! [1] //! [2] map.insert("twelve", 12); //! [2] //! [3] int num1 = map["thirteen"]; int num2 = map.value("thirteen"); //! [3] //! [4] int timeout = 30; if (map.contains("TIMEOUT")) timeout = map.value("TIMEOUT"); //! [4] //! [5] int timeout = map.value("TIMEOUT", 30); //! [5] //! [6] // WRONG QMap map; ... for (int i = 0; i < 1000; ++i) { if (map[i] == okButton) cout << "Found button at index " << i << Qt::endl; } //! [6] //! [7] QMapIterator i(map); while (i.hasNext()) { i.next(); cout << i.key() << ": " << i.value() << Qt::endl; } //! [7] //! [8] QMap::const_iterator i = map.constBegin(); while (i != map.constEnd()) { cout << i.key() << ": " << i.value() << Qt::endl; ++i; } //! [8] //! [9] map.insert("plenty", 100); map.insert("plenty", 2000); // map.value("plenty") == 2000 //! [9] //! [12] QMap map; ... foreach (int value, map) cout << value << Qt::endl; //! [12] //! [13] #ifndef EMPLOYEE_H #define EMPLOYEE_H class Employee { public: Employee() {} Employee(const QString &name, QDate dateOfBirth); ... private: QString myName; QDate myDateOfBirth; }; inline bool operator<(const Employee &e1, const Employee &e2) { if (e1.name() != e2.name()) return e1.name() < e2.name(); return e1.dateOfBirth() < e2.dateOfBirth(); } #endif // EMPLOYEE_H //! [13] //! [14] QMap map; ... QMap::const_iterator i = map.find("HDR"); while (i != map.end() && i.key() == "HDR") { cout << i.value() << Qt::endl; ++i; } //! [14] //! [15] QMap map; map.insert(1, "one"); map.insert(5, "five"); map.insert(10, "ten"); map.lowerBound(0); // returns iterator to (1, "one") map.lowerBound(1); // returns iterator to (1, "one") map.lowerBound(2); // returns iterator to (5, "five") map.lowerBound(10); // returns iterator to (10, "ten") map.lowerBound(999); // returns end() //! [15] //! [16] QMap map; ... QMap::const_iterator i = map.lowerBound("HDR"); QMap::const_iterator upperBound = map.upperBound("HDR"); while (i != upperBound) { cout << i.value() << Qt::endl; ++i; } //! [16] //! [17] QMap map; map.insert(1, "one"); map.insert(5, "five"); map.insert(10, "ten"); map.upperBound(0); // returns iterator to (1, "one") map.upperBound(1); // returns iterator to (5, "five") map.upperBound(2); // returns iterator to (5, "five") map.upperBound(10); // returns end() map.upperBound(999); // returns end() //! [17] //! [18] QMap map; map.insert("January", 1); map.insert("February", 2); ... map.insert("December", 12); QMap::iterator i; for (i = map.begin(); i != map.end(); ++i) cout << i.key() << ": " << i.value() << Qt::endl; //! [18] //! [19] QMap::iterator i; for (i = map.begin(); i != map.end(); ++i) i.value() += 2; //! [19] //! [20] QMap::iterator i = map.begin(); while (i != map.end()) { if (i.key().startsWith('_')) i = map.erase(i); else ++i; } //! [20] //! [21] QMap::iterator i = map.begin(); while (i != map.end()) { QMap::iterator prev = i; ++i; if (prev.key().startsWith('_')) map.erase(prev); } //! [21] //! [22] // WRONG while (i != map.end()) { if (i.key().startsWith('_')) map.erase(i); ++i; } //! [22] //! [23] if (i.key() == "Hello") i.value() = "Bonjour"; //! [23] //! [24] QMap map; map.insert("January", 1); map.insert("February", 2); ... map.insert("December", 12); QMap::const_iterator i; for (i = map.constBegin(); i != map.constEnd(); ++i) cout << i.key() << ": " << i.value() << Qt::endl; //! [24] //! [25] QMultiMap map1, map2, map3; map1.insert("plenty", 100); map1.insert("plenty", 2000); // map1.size() == 2 map2.insert("plenty", 5000); // map2.size() == 1 map3 = map1 + map2; // map3.size() == 3 //! [25] //! [26] QList values = map.values("plenty"); for (int i = 0; i < values.size(); ++i) cout << values.at(i) << Qt::endl; //! [26] //! [27] QMultiMap::iterator i = map.find("plenty"); while (i != map.end() && i.key() == "plenty") { cout << i.value() << Qt::endl; ++i; } //! [27] //! [keyiterator1] for (QMap::const_iterator it = map.cbegin(), end = map.cend(); it != end; ++it) { cout << "The key: " << it.key() << Qt::endl cout << "The value: " << it.value() << Qt::endl; cout << "Also the value: " << (*it) << Qt::endl; } //! [keyiterator1] //! [keyiterator2] // Inefficient, keys() is expensive QList keys = map.keys(); int numPrimes = std::count_if(map.cbegin(), map.cend(), isPrimeNumber); qDeleteAll(map2.keys()); // Efficient, no memory allocation needed int numPrimes = std::count_if(map.keyBegin(), map.keyEnd(), isPrimeNumber); qDeleteAll(map2.keyBegin(), map2.keyEnd()); //! [keyiterator2] //! [28] QMap map; map.insert("January", 1); map.insert("February", 2); // ... map.insert("December", 12); for (auto [key, value] : map.asKeyValueRange()) { cout << key << ": " << value << Qt::endl; --value; // convert to JS month indexing } //! [28]