Javascript 对象 : backreference to property name

Question

我正在尝试简化 javascript 对象内容的创建，以便值取决于成员名称，如下所示:

var obj = {
    1: "you selected 1",
    2: "wow, you selected 2",
    3: "this time, you selected " + myName(), //myName() gets resolved to 3
    137: "I think you've chosen " + myName() + " this time.", //myName() gets resolved to 137
    513: myName() + " is the answer!" //myName() gets resolved to 513
};

是否有可能在值的定义中反向引用成员名称，使用类似假定函数 myName() 的方法？

如果不存在本地方法，推荐的方法是什么？

你可能会问“为什么这家伙需要这种奇怪的方式来生成对象？”，答案是:在我的代码中，成员/字段名称可能会改变，默认值会被复制唯一的区别是对成员名称的引用，我不想在每个键值对中定义数字值两次，因此我采用了一种在值定义中反向引用名称的方法。

Answer 1

您正在寻找 ES6 功能，Proxy

The Proxy object is used to define custom behavior for fundamental operations (e.g. property lookup, assignment, enumeration, function invocation, etc).

然后使用实际 key 获取 prop 并将占位符 {key} 替换为实际 key 。

var obj = {
        1: "you selected {key}",
        2: "wow, you selected {key}",
        3: "this time, you selected {key}",
        137: "I think you've chosen {key} this time.",
        513: "{key} is the answer!"
    },
    p = new Proxy(obj, {
        get: function(target, prop) {
            return target[prop] && target[prop].replace("{key}", prop);
        }
    });

console.log(p[3]);          // this time, you selected 3
console.log(p[137]);        // I think you've chosen 137 this time.
console.log(p[513]);        // 513 is the answer!
obj.foo = 'This is {key}!'; // create new property foo
console.log(p.foo);         // This is foo!
obj.bar = obj.foo;          // assign foo to bar
delete obj.foo;             // delete foo
console.log(p.foo);         // undefined
console.log(p.bar);         // This is bar!