面试题：TypeScript复杂数据类型声明与函数重载

Question

编写一段TypeScript代码，声明一个名为`User`的接口，包含`name`（字符串类型）、`age`（数字类型）和`hobbies`（字符串数组类型）属性。然后编写一个函数`printUserInfo`，它有两种重载形式：一种接受`User`类型参数直接打印用户信息；另一种接受`name`（字符串）和`age`（数字）作为参数，先创建`User`对象再打印信息。

Answer 1

interface User {
    name: string;
    age: number;
    hobbies: string[];
}

function printUserInfo(user: User): void;
function printUserInfo(name: string, age: number): void;
function printUserInfo(arg1: User | string, arg2?: number) {
    let user: User;
    if (typeof arg1 ==='string') {
        user = {
            name: arg1,
            age: arg2!,
            hobbies: []
        };
    } else {
        user = arg1;
    }
    console.log(`Name: ${user.name}, Age: ${user.age}, Hobbies: ${user.hobbies.join(', ')}`);
}