js 将对象转换成json

let person = {
    name: "John",
    age: 30,
    city: "New York"
};

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

function stringifyWithCircularReference(obj) {
    const seen = new WeakSet();
    return JSON.stringify(obj, (key, value) => {
        if (typeof value === 'object' && value !== null) {
            if (seen.has(value)) {
                return '[Circular]';
            }
            seen.add(value);
        }
        return value;
    });
}

let a = {};
let b = { a };
a.b = b;
console.log(stringifyWithCircularReference(a)); // 输出: {"b":{"a":"[Circular]"}}

let person = {
    name: "John",
    age: 30,
    password: "secret"
};

let jsonString = JSON.stringify(person, (key, value) => {
    if (key === 'password') return undefined; // 忽略password属性
    return value;
});
console.log(jsonString); // 输出: {"name":"John","age":30}