如何防止JS错误“无法销毁...”?

时间:2019-03-01 22:00:51

标签: javascript arrays ecmascript-6 es6-promise

如何防止此代码中的错误“无法破坏未定义或null的字段”:

const [{ field }, { field2 }] = await Promise.all([asynchronous operations...])

1 个答案:

答案 0 :(得分:0)

这是使用第三方库(async-af)的一种可能的解决方案。

const input = [Promise.resolve(null), Promise.resolve({field2: 'b'})];

(async () => {
  const [{field}, {field2}] = await AsyncAF(input).map(
    result => result != null ? result : {field: null, field2: null}
  );
  console.log(field, field2);
})();
<script src="https://unpkg.com/async-af@7.0.10/index.js"></script>


或者,如果您想要使用默认值:

const input = [Promise.resolve(null), Promise.resolve({field2: 'b'})];

(async () => {
  const [{field = 'defaultValue'}, {field2 = 'defaultValue'}] = await AsyncAF(input)
    .map(result => result != null ? result : {});
  console.log(field, field2);
})();
<script src="https://unpkg.com/async-af@7.0.10/index.js"></script>