HarmonyOS 对于已知的JsonObject如何向其添加数据

解析：

const str = '{"id": "123", "username": "john"}';
let user = JSON.parse(str);

添加或修改：

let rec: Record<string, number | string | boolean> = JSON.parse('{ "u": 123, "v" : "abc", "w" : true }')
rec['add'] = "新增";
rec['u'] = 456;
let info: string = JSON.stringify(rec);

let rec2: object = JSON.parse('{ "u": 123, "v" : "abc", "w" : true }')
rec2['add2'] = "新增2";
rec2['u'] = 789;
let info2: string = JSON.stringify(rec2);

let rec: Record<string, number | string | boolean> = JSON.parse('{}');
rec['add'] = "新增";
rec['u'] = 456;
let info: string = JSON.stringify(rec);
console.log("maotest", info);

遍历：

let rec: Record<string, number | string | boolean> = JSON.parse('{ "u": 123, "v" : "abc", "w" : true }')
let keys = Object.keys(rec)
let values = Object.values(rec)
for (let item of Object.entries(rec)) {
  let key = item[0];
  let value = item[1];
}

查找删除：

import { JSON } from '@kit.ArkTS';
let rec: Record<string, number | string | boolean> = JSON.parse('{ "u": 123, "v" : "abc", "w" : true }')
JSON.has(rec, 'v')
JSON.remove(rec, 'v');