Question

我创建了一个文件GetSetStorage include AsyncStorage，当我尝试使用它时，我发现它无效。

这是我的GetSetStorage文件：

import { AsyncStorage } from 'react-native';

class GetSetStorage {
  setStorageAsync(key, value) {
    console.log('start set storage');
    console.log(`key =>${key}`);
    console.log(`vaue =>${value}`);
    return new Promise((resolve, reject) => {
      console.log('Why is no working here ?');
      AsyncStorage.setItem(key, value, (error) => {
      console.log(error);
        if (error) {
          console.log('===');
          console.log(`set${key}error${error}`);
          console.log('===');
          reject(`set${key}error${error}`);
        } else {
          console.log('===');
          console.log(`set${key}succeed`);
          console.log('===');
          resolve(true);
        }
      });
    });
  }

  getStorageAsync(key) {
    return new Promise((resolve, reject) => {
      AsyncStorage.getItem(key, (error, result) => {
        console.log(error);
        console.log('where is my error');
        if (error) {
          console.log('===');
          console.log(`load ${key} error ${error}`);
          console.log('===');
          reject(`load ${key} erro ${error}`);
        } else {
          console.log('===');
          console.log(`load ${key} succeed`);
          console.log('===');
          resolve(result);
        }
      });
    });
  }
}

export default new GetSetStorage();

我在我的组件中使用它：

import GetSetStorage from '../storage/GetSetStorage';

  componentWillMount() {
    GetSetStorage.setStorageAsync('testKey', 'test value');
  }

我看到我的console.log，我发现setItem无效。为什么？

任何帮助将不胜感激。提前谢谢。

Answer 1

Asyncstorage还会返回一个promise，因此您可以执行类似

的操作

AsyncStorage.setItem('email', JSON.stringify(this.state.UserEmail))
  .then(() => console.log('saved email successfully'))
  .catch(err => console.error('something went wrong', err));

同样，要获取相同的密钥，您可以执行以下操作：

AsyncStorage.getItem('email')
.then(val => {
  if (val !== null) console.log(val); // You can do whatever you want with the email
})
.catch(err => console.error(err)) // if there was an error fetching data

请注意，如果异步存储中没有任何内容，则会返回＆＃39; null＆＃39;所以为了处理错误，你需要将它们放在if语句而不是catch

中

Answer 2

//检查出来！

return Stream.of((int)levenshteinScore, reverseComparison, regionStart, regionLength).map(Match::new);


public static class Match{
    // Properties
    public int levenshteinSimilarity;
    public boolean reverseComparison;
    public int regionStart;
    public int regionLength;

    // Constructor
    public Match(int levenshteinSimilarity, boolean reverseComparison, int regionStart, int regionLength){
        this.levenshteinSimilarity = levenshteinSimilarity;
        this.reverseComparison = reverseComparison;
        this.regionStart = regionStart;
        this.regionLength = regionLength;
    }
}

为什么使用AsyncStorage.setItem是不是没有wroking？

2 个答案: