TypeScript:使用排列运算符指定值必须在Array中

Question

我正在尝试定义一个类型，其中favoriteFruit属性的值必须是选项数组中的项。其中选项数组是动态/未知的(使得不可能使用并集类型"|"(。

const options = ["apple", "orange", "kiwi"]; // Dynamic list that can be modified in the future 
type Person =  {
name: string;
favoriteFruit: /* --- val in [...options] --- */
};
const personA:Person = {name: "Jack", favoriteFruit: "apple"}; // OK
const personB:Person = {name: "John", favoriteFruit: "orange"}; // OK
const personC:Person = {name: "Jane", favoriteFruit: "banana"}; // ERROR

Answer 1

我希望这就是您想要的

[更新]

const options = ["apple", "orange", "kiwi"] as const; // Dynamic list that can be modified in the future 
type optionsType = typeof options[number];
type Person =  {
name: string;
favoriteFruit: optionsType;/* --- val in [...options] --- */
};
const personA:Person = {name: "Jack", favoriteFruit: "apple"}; // OK
const personB:Person = {name: "John", favoriteFruit: "orange"}; // OK
const personC:Person = {name: "Jane", favoriteFruit: "banana"}; // ERROR
console.log(personC)

你可以保持你的选项列表动态

你可以在这里测试

Answer 2

我发现：如何将字符串数组转换为typescript类型。

const arr = ["foo", "bar", "loo"] as const
type arrTyp = typeof arr[number]; // "foo" | "bar" | "loo"