我有一个对象数组和字符串数组
cities = [ { id: '1', name: 'Paris'}, { id: '2', name: 'Rome'}, { id: '3', name: 'London'}, { id: '4', name: 'Barcelona'}]
userChoice = ['2','4']
我需要使用userChoice遍历城市,并通过ID查找城市名称。我想这将是一个嵌套循环,但我为此感到困惑。
cities.filter(city=> userChoice.forEach(choice => choice == city.id))
您可以使用filter()和includes()通过检查cities
数组中是否存在城市的id
来过滤userChoice
数组。
仅获取名称,可以使用map()转换结果。
let cities = [ { id: '1', name: 'Paris'}, { id: '2', name: 'Rome'}, { id: '3', name: 'London'}, { id: '4', name: 'Barcelona'}];
let userChoice = ['2','4'];
let filteredCities = cities.filter(city => userChoice.includes(city.id));
let names = filteredCities.map(city => city.name);
console.log(names);
您可以使用Map对象根据城市查询ID。
let cityMap = new Map(cities.map(c => [c.name, c.id]));
console.log(cityMap.get("Rome")); // --> "2"
只需使用简单的地图,您就可以将数组元素从另一个数组映射到城市。如果您可以包含数组中可能不包含的值,但为简单起见,我可能会忽略它。
const cities = [ { id: '1', name: 'Paris'}, { id: '2', name: 'Rome'}, { id: '3', name: 'London'}, { id: '4', name: 'Barcelona'}];
const userChoice = ['2','4'];
const userCities = userChoice.map(val => cities.find(c => c.id === val).name);
console.log(userCities)