未捕获(在promise中)长度:无法读取null的属性‘TypeError’

someAsyncFunction()
  .then(result => {
    if (result !== null && result !== undefined) {
      // 安全地访问属性
      console.log(result.length);
    } else {
      console.error('Result is null or undefined');
    }
  })
  .catch(error => {
    console.error('An error occurred:', error);
  });

someAsyncFunction()
  .then(result => {
    console.log(result?.length); // 如果result是null或undefined，这里不会抛出错误
  })
  .catch(error => {
    console.error('An error occurred:', error);
  });

someAsyncFunction()
  .then(result => {
    if (result) {
      console.log(result.length);
    } else {
      console.error('Invalid result:', result);
    }
  })
  .catch(error => {
    console.error('An error occurred:', error);
  });