js list json

let jsonString = '{"name":"John", "age":30, "city":"New York"}';
let jsonObject = JSON.parse(jsonString);
console.log(jsonObject.name); // 输出: John

let obj = {
    name: "John",
    age: 30,
    city: "New York"
};
let jsonString = JSON.stringify(obj);
console.log(jsonString); // 输出: {"name":"John","age":30,"city":"New York"}

let jsonArrayString = '[{"name":"John","age":30},{"name":"Anna","age":22}]';
let jsonArray = JSON.parse(jsonArrayString);
jsonArray.forEach(person => {
    console.log(person.name + " is " + person.age + " years old.");
});
// 输出:
// John is 30 years old.
// Anna is 22 years old.

let invalidJsonString = '{"name":"John", "age":30,, "city":"New York"}'; // 注意这里有两个逗号
try {
    let jsonObject = JSON.parse(invalidJsonString);
} catch (error) {
    console.error("JSON解析错误:", error);
}

let obj = {};
obj.self = obj; // 创建循环引用

// 使用replacer参数移除循环引用
let jsonString = JSON.stringify(obj, function(key, value) {
    if (key === 'self') return undefined;
    return value;
});
console.log(jsonString); // 输出: {}