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This article mainly shares the React Native AsyncStorage local storage tool class for everyone, which has certain reference value. Interested friends can refer to it and hope it can help everyone.
Use the react-native component AsyncStorage to save local data through promise. The specific content is as follows
import {AsyncStorage} from 'react-native'; export default class StorageUtil { /** * 保存一个Json对象 * @param key * @param value * @param callback */ static async saveJsonObject(key, value) { return await this.saveString(key, JSON.stringify(value)); } /** * 获取一个Json对象 * @param key * @param defaultObject */ static async getJsonObject(key, defaultObject) { let result=null; try{ result=await this.getString(key,null); result=await JSON.parse(result); }catch (err){ if(defaultObject){ return Promise.resolve(defaultObject); }else{ return Promise.reject(err); } } return result; } /** * 保存一个值 * @param key * @param value */ static async saveString(key, value) { if (key != null && value != null) { //Key 与Value 都不为空 try { await AsyncStorage.setItem(key, value) } catch (err) { return Promise.reject(err) } return Promise.resolve(true); } else { return Promise.reject({"msg": "Key and value can not be null"}); } } /** * 获取一个值 * @param key * @param defaultValue */ static async getString(key, defaultValue) { let result = null; let noDataError = {"msg": "No value found !"}; if (key != null) { result = await AsyncStorage.getItem(key); // console.log('get string result',result,defaultValue); return result ? result : defaultValue!=null ? defaultValue : Promise.reject(noDataError); } else { if (defaultValue) { return Promise.resolve(defaultValue); } else { return Promise.reject(noDataError); } } } /** * 移除一个值 * @param key */ static async remove(key) { let result = true; try { result = await AsyncStorage.removeItem(key); } catch (err) { return Promise.reject(err) } return result; } /** * 获取所有已存储 */ static async getAllKeys() { let result=true; try { result = await AsyncStorage.getAllKeys(); } catch (err) { return Promise.reject(err) } return result; } }
External calls
Save
StorageUtil.saveJsonObject(KEY_LOCAL_USER_INFO, user);
Read
StorageUtil.getJsonObject(KEY_LOCAL_USER_INFO).then(data=>{console.log(data))}
Clear
StorageUtil.remove(KEY_LOCAL_USER_INFO)
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