js array转换成json

let arr = [1, 2, 3, {name: "John", age: 30}];
let jsonStr = JSON.stringify(arr);
console.log(jsonStr); // 输出: [1,2,3,{"name":"John","age":30}]

let obj = {};
obj.self = obj;
JSON.stringify(obj); // 抛出错误: TypeError: Converting circular structure to JSON

function stringifyWithoutCircular(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 obj = {};
obj.self = obj;
console.log(stringifyWithoutCircular(obj)); // 输出: {"self":"[Circular]"}

let arr = ['Hello\nWorld', 'This is a "test"'];
let jsonStr = JSON.stringify(arr);
console.log(jsonStr); // 输出: ["Hello\\nWorld","This is a \"test\""]