您可以使用country-data npm软件包
用途

const countryData = require("country-data");

const getCountryCodeAndCurrency = (countryCode) => {
    const country = countryData.countries[countryCode];

    return country
        ? { code: country.alpha3, currency: country.currencies[0] }
        : null;
};

console.log(getCountryCodeAndCurrency('IN')); // {"code":"IND","currency":"INR"}
console.log(getCountryCodeAndCurrency('US')); // {"code":"USA","currency":"USD"}

看起来你有很多艰苦的工作要做。我不相信有一个预制的数据库，但你可以很容易地实现它与一个简单的对象。

const currencies = {
  "us": { code: "USD", country: "USA" },
  "in": { code: "INR", country: "IND" },
  // ...
}

currencies["in"] // <-- { code: "INR", country: "IND" }