Question

我想使用AsyncStorage作为设置并获取值，但它在componentDidMount内不起作用：

componentDidMount(){

    commonHelper.setData('mmmm','12345');
    commonHelper.getData('mmmm')
    .then(data => {
      console.log(data)
    });

 }

我的commonHelper.js

function getData(key) {
  try {
       const value = AsyncStorage.getItem(key).then(val => {
         return val
       });
       return value
     } catch (err) {
       throw err
     }
}

function setData(key,value) {
  try {
    AsyncStorage.setItem(key, value);
  } catch (error) {
    console.log("Error saving data" + error);
  }
}

Answer 1

按照Dan的建议，异步使用它：

import { setData } from './commonHelper';

  ...

  componentDidMount(){
    commonHelper.setData('mmmm','12345')
    .then(() => { /* do something. The data is stored now. */});
  }


//commonHelper.js

export async function setData(key, value) {
  try {
    await AsyncStorage.setItem(key, value);
  } catch (error) {
    console.log("Error saving data" + error);
  }
}

Answer 2

import { setData } from '../commonHelper';

componentDidMount() {
  this.updateStorage();
}

updateStorage = async () => {
  const item = await setData('mmmm','12345');
  console.log({
    item
  });
}

CommonHelper函数：

export const setData = async (key, value) => {
  const item = await AsyncStorage.setItem(key, value);
  return item;
}

AsyncStorage不起作用-反应本机

2 个答案: