JavaScript自带Map字典类

const map = new Map();

map.set(\'Gandalf\', \'gandalf@email.com\');
map.set(\'John\', \'johnsnow@email.com\');
map.set(\'Tyrion\', \'tyrion@email.com\');

console.log(map.has(\'Gandalf\')); // true
console.log(map.size); // 3

console.log(map.keys()); // MapIterator {"Gandalf", "John", "Tyrion"}
console.log(map.values()); // MapIterator {"gandalf@email.com", "johnsnow@email.com", "tyrion@email.com"}
console.log(map.get(\'Tyrion\')); // tyrion@email.com

map.delete(\'John\');

console.log(map.keys()); // MapIterator {"Gandalf", "Tyrion"}
console.log(map.values()); // MapIterator {"gandalf@email.com", "tyrion@email.com"}