javascript - 如何使用枚举值作为数组的索引

Question

我尝试使用枚举值作为数组的索引，但它给我一个错误。

export class Color {
    static RED = 0;
    static BLUE = 1;
    static GREEN = 2;
}

let x = ['warning', 'info', 'success'];
let anotherVariable = x[Color.RED]; <---- Error: Type 'Color' cannot be used as an index type.

我尝试将 Number() 和 parseInt 转换为数字，但它不起作用。

有什么方法可以将枚举值用作索引吗？

Answer 1

为了创建一个枚举，我们创建了一个常量卡住对象。对于差异和原因，请参阅以下引用:

const applies to bindings ("variables"). It creates an immutable binding, i.e. you cannot assign a new value to the binding.

Object.freeze works on values, and more specifically, object values. It makes an object immutable, i.e. you cannot change its properties.

发件人:https://stackoverflow.com/a/33128023/9758920

之后我们仍然可以像访问普通对象一样访问键和值。

// https://stackoverflow.com/questions/287903/what-is-the-preferred-syntax-for-defining-enums-in-javascript
const COLORS = Object.freeze({"RED":0, "BLUE":1, "GREEN":2})

let x = ['warning', 'info', 'success'];
let anotherVariable = x[COLORS.RED]; 

console.log(anotherVariable)

另请查看:https://stackoverflow.com/a/49309248/9758920