如何用Rust编程访问未知结构的json串？

如何用Rust访问未知结构的JSON串，并包含对数组的访问？以下是一个简单的示例：

use serde_json::{
   Value};

fn main() {
   
    let json_str = r#"{"name":"John","age":30,"city":"New York","hobbies":["reading","coding","gaming"]}"#;

    // 解析JSON字符串
    let json: Value = serde_json::from_str(json_str).unwrap();

    // 访问特定的属性
    if let Some(name) = json.get("name") {
   
        println!("Name: {}", name);
    }
    if let Some(age) = json.get("age") {
   
        println!("Age: {}", age);
    }
    if let Some(city) = json.get("city") {
   
        println!("City: {}", city);
    }

    // 访问数组
    if let Some(hobbies) = json.get("hobbies") {
   
        if let Some(hobbies_array) = hobbies.as_array() {
   
            for hobby in hobbies_array {
   
                if let Some(hobby_str) = hobby.as_str() {
   
                    println!("Hobby: {}", hobby_str);
                }
            }
        }
    }
}