如何在React Native中使用AsyncStorage正确获取Item? [英] How to properly getItem with AsyncStorage in React Native?

问题描述

我当前的项目要求我在本地存储用户数据，因此我使用React Native本身的AsyncStorage.但是我在如何检索已经保存的数据时遇到了一些问题，但我总是会得到null，但是却以某种方式保存了数据.

My current project require me to store user data locally, So I use the AsyncStorage from react native itself. However I got some issues on how to retrieve already saved data I always get null but somehow the data is saved..

我总是

{_45:0，_81:0，_65:null，_54:null}

{ _45: 0, _81: 0, _65: null, _54: null }

这是我的代码，这是react native文档中的简单示例

and here's my code, which is the simple example from react native documentation

AsyncStorage.setItem('baru', 'this is new dude!!');
var b = AsyncStorage.getItem('baru');
console.log(b);

推荐答案

阅读

静态getItem(键，回调?) 获取键的项目，并在完成时调用回调.返回一个Promise对象.

static getItem(key, callback?) Fetches an item for a key and invokes a callback upon completion. Returns a Promise object.

您需要兑现承诺.我建议您使用(作为文档)async/await.因此，例如，您可以执行以下操作:

You need to handle that promise. I'd recommend you to use (as the docs) async/await. So for example you can do:

async function getItem(item) {
  try {
    const value = await AsyncStorage.getItem(item);
    console.log(value);
    return value;
  } catch (error) {
    // Handle errors here
  }
}

您实际上也应该对setItem做类似的事情.

You should actually do something similar for setItem too.

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