给定一个像这样的 countries
数组:
const countries = [
{ name: "Australia", code: "AU" },
{ name: "Japan", code: "JP" },
{ name: "Norway", code: "NO" },
{ name: "Russian Federation", code: "RU" }
];
生成以下类型的最简单方法是什么?
type CountryCodes = "" | "AU" | "JP" | "NO" | "RU";
注意:多了一个空字符串。
最佳答案
虽然这个函数从JS的角度来说是没用的。它能够将代码统一为一种类型。
function createCountries<T extends string>(
contries: { name: string; code: T }[],
): { name: string; code: T }[] {
return contries;
}
const countries = createCountries([
{ name: "Australia", code: "AU" },
{ name: "Japan", code: "JP" },
{ name: "Norway", code: "NO" },
{ name: "Russian Federation", code: "RU" }
]);
type CountryCodes = "" | (typeof countries)[number]["code"]; // "" | "AU" | "JP" | "NO" | "RU";
// Example - How to use the type
function getCountryByCode(code: CountryCode): Country | undefined {
return countries.find(country => country.code == code);
}
国家
的类型:
{
name: string;
code: "AU" | "JP" | "NO" | "RU";
}[]
没有进一步的信息,这是你能做的最好的...
type Countries = { name: string; code: string }[];
const countriesAbc = [
{ name: "Australia", code: "AU" },
{ name: "Japan", code: "JP" },
{ name: "Norway", code: "NO" },
{ name: "Russian Federation", code: "RU" }
] as const;
const countries: Countries = [...countriesAbc];
type CountryCodes = "" | (typeof countriesAbc)[number]["code"]; // "" | "AU" | "JP" | "NO" | "RU";
关于typescript - 如何从 TypeScript 中的对象数组创建类型?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/66134523/