JavaScript中函数作为对象属性的赋值与JSON序列化行为解析

const myObject = {};
myObject.greet = function(name) {
  console.log(`Hello, ${name}!`);
};

myObject.greet('World'); // 输出: Hello, World!

const logger = {
  info: console.log, // 简化logger为console.log
};

function generate_api_calls(app_name) {
  let api_calls = {};
  api_calls['cameraFeed'] = `http://localhost:5051/camera/feed`; // 示例URL

  let ff;
  let items = [1, 2, 3, 4];
  for (let i in items) {
    let name = items[i];
    function bar(j) {
      logger.info(`bar ${j}`);
    };

    bar(i); // 函数 bar 被正常调用
    ff = bar; // 函数 bar 被赋值给 ff
    api_calls[name] = bar; // 函数 bar 被赋值给 api_calls 的属性

    // 第一次打印：尝试序列化整个 api_calls 对象
    logger.info(`generate_api_calls api ${name} ${JSON.stringify(api_calls)}`);
    // 第二次打印：尝试序列化 api_calls[name] 这个函数本身
    logger.info(`generate_api_calls api ${JSON.stringify(api_calls[name])}`);
  }
  ff('00'); // 函数 ff（即 bar）被正常调用

  logger.info(`generate_api_calls 5 ${JSON.stringify(api_calls)}`);
  return api_calls;
}

generate_api_calls('test');

bar 0
generate_api_calls api 1 {"cameraFeed":"http://localhost:5051/camera/feed"}
generate_api_calls api undefined
bar 1
generate_api_calls api 2 {"cameraFeed":"http://localhost:5051/camera/feed"}
generate_api_calls api undefined
...
bar 00
generate_api_calls 5 {"cameraFeed":"http://localhost:5051/camera/feed"}

const logger = {
  info: console.log,
};

function generate_api_calls(app_name) {
  let api_calls = {};

  api_calls['cameraFeed'] = 'cameraFeed_URL'; // 简化URL

  let ff;
  let items = [1, 2, 3, 4];
  for (let i in items) {
    let name = items[i];

    function bar(j) {
      logger.info(`bar ${j}`);
    };

    bar(i);
    ff = bar;
    api_calls[name] = bar;

    // *** 关键验证点：直接打印 api_calls[name] ***
    console.log(`验证：属性 '${name}' 上的函数为:`, api_calls[name]); 

    logger.info(`generate_api_calls api ${name} ${JSON.stringify(api_calls)}`);
    logger.info(`generate_api_calls api ${JSON.stringify(api_calls[name])}`);
  }
  ff('00');

  // *** 关键验证点：直接打印完整的 api_calls 对象 ***
  console.log('验证：完整的api_calls对象:', api_calls);

  logger.info(`generate_api_calls 5 ${JSON.stringify(api_calls)}`);
  return api_calls;
}

generate_api_calls('test');

console.log('\n--- JSON.stringify 对不同类型的处理示例 ---');
console.log(JSON.stringify({
  data: 'abc',
  func: () => { console.log('This is a function'); }, // 函数会被忽略
  undef: undefined, // undefined 会被忽略
  sym: Symbol('test'), // Symbol 会被忽略
  num: 123
}));

bar 0
验证：属性 '1' 上的函数为: [Function: bar] // 这里明确显示了函数对象
generate_api_calls api 1 {"cameraFeed":"cameraFeed_URL"}
generate_api_calls api undefined
bar 1
验证：属性 '2' 上的函数为: [Function: bar]
generate_api_calls api 2 {"cameraFeed":"cameraFeed_URL"}
generate_api_calls api undefined
...
bar 00
验证：完整的api_calls对象: {
  cameraFeed: 'cameraFeed_URL',
  '1': [Function: bar],
  '2': [Function: bar],
  '3': [Function: bar],
  '4': [Function: bar]
}
generate_api_calls 5 {"cameraFeed":"cameraFeed_URL"}

--- JSON.stringify 对不同类型的处理示例 ---
{"data":"abc","num":123} // func, undef, sym 被忽略