如何使用变量将键添加到 javascript 哈希映射中

Question

// Create the hashmap
var animal = {};
// Add keys to the hashmap
animal[‘cat’] = { sound: ‘meow’, age:8 };
animal[‘dog’] = { sound: ‘bark’, age:10 };
animal[‘bird’] = { sound: ‘tweet’, age:2 };
animal[‘cow’] = { sound: ‘moo’, age:5 };

我正在使用上面的代码来尝试创建哈希图。我的问题是，声音和年龄的位置，我将如何使用变量放置它们。

例如

var one = 'sound';
var two = 'age';
animal['cat'] = {one: 'meow', two: 9};

Answer 1

在 ES2015+ 中它是

var one = 'sound';
var two = 'age';
animal['cat'] = {[one]: 'meow', [two]: 9};

通过转译器（例如 babel）运行它，你会得到

var _animal$cat;
var one = 'sound';
var two = 'age';
animal['cat'] = (_animal$cat = {}, _animal$cat[one] = 'meow', _animal$cat[two] = 9, _animal$cat);

Answer 2

var animal = {};
var one = 'sound';
var two = 'age';
animal['cat'] = {};
animal['cat'][one] = 'meow';
animal['cat'][two] = 9;
console.log(animal);