如何在对象形状上使用keyof而不是显式类型

type Keys = keyof T;

interface Person {
  name: string;
  age: number;
  address: string;
}

type PersonKeys = keyof Person; // "name" | "age" | "address"

function printPerson(person: Person) {
  for (let key in person) {
    console.log(key + ": " + person[key]);
  }
}

function getProperty<T, K extends keyof T>(obj: T, key: K) {
  return obj[key];
}

const person: Person = {
  name: "John",
  age: 30,
  address: "123 Main St"
};

const name = getProperty(person, "name"); // "John"
const age = getProperty(person, "age"); // 30
const address = getProperty(person, "address"); // "123 Main St"