Javascript 如何在typescript中指定枚举的索引类型

考虑以下示例：

enum Color {
    Green = "green",
    Red = "red"

}

let index : keyof Color
index = "Green" 

console.log(Color[index])

错误

索引变量必须是枚举颜色键的字符串版本。

---

如何指定索引变量的类型？

您应该使用

let index:keyof typeof Color

，因为

Color

实际上是一个对象（排序字典），所以您需要首先使用

typeof

获取其类型。要深入解释

keyof

和

typeof

的功能，请参阅

---

请参阅上的工作示例。

可能：

let index:keyof typeof Color

Type '"Green"' is not assignable to type 'number | "toString" | "charAt" | "charCodeAt" | "concat" | "indexOf" | "lastIndexOf" | "localeCompare" | "match" | "replace" | "search" | "slice" | "split" | "substring" | "toLowerCase" | ... 27 more ... | "padEnd"'.
Element implicitly has an 'any' type because expression of type 'number | "toString" | "charAt" | "charCodeAt" | "concat" | "indexOf" | "lastIndexOf" | "localeCompare" | "match" | "replace" | "search" | "slice" | "split" | "substring" | "toLowerCase" | ... 27 more ... | "padEnd"' can't be used to index type 'typeof Color'. No index signature with a parameter of type 'number' was found on type 'typeof Color'.

enum Color {
    Green = "green",
    Red = "red"

}

let index: keyof typeof Color;
index = "Green" 

console.log(Color[index])