根据键值追加列表列表

# 创建一个字典列表
data = [
    {"id": 1, "name": "Alice", "age": 30},
    {"id": 2, "name": "Bob", "age": 25},
    {"id": 3, "name": "Charlie", "age": 35}
]

# 根据键值追加新的键值对
for item in data:
    if item["id"] == 2:
        item["city"] = "New York"

print(data)

// 创建一个对象数组
let data = [
    { id: 1, name: "Alice", age: 30 },
    { id: 2, name: "Bob", age: 25 },
    { id: 3, name: "Charlie", age: 35 }
];

// 根据键值追加新的键值对
data.forEach(item => {
    if (item.id === 2) {
        item.city = "New York";
    }
});

console.log(data);

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class Main {
    public static void main(String[] args) {
        // 创建一个列表，其中包含多个HashMap
        List<Map<String, Object>> data = new ArrayList<>();
        Map<String, Object> item1 = new HashMap<>();
        item1.put("id", 1);
        item1.put("name", "Alice");
        item1.put("age", 30);
        data.add(item1);

        Map<String, Object> item2 = new HashMap<>();
        item2.put("id", 2);
        item2.put("name", "Bob");
        item2.put("age", 25);
        data.add(item2);

        Map<String, Object> item3 = new HashMap<>();
        item3.put("id", 3);
        item3.put("name", "Charlie");
        item3.put("age", 35);
        data.add(item3);

        // 根据键值追加新的键值对
        for (Map<String, Object> item : data) {
            if ((int) item.get("id") == 2) {
                item.put("city", "New York");
            }
        }

        System.out.println(data);
    }
}

if key not in dictionary:
    dictionary[key] = value

if isinstance(key, int) and isinstance(value, str):
    dictionary[key] = value

from collections import defaultdict

data = defaultdict(dict)
data[1]["name"] = "Alice"