Question

我是新的反应原生，我现在只是学习反应本机，我试图通过单击注册按钮存储来自TextInput的值并存储到AsyncStorage。我试图通过单击获取按钮来获取该值。我可以＆＃ 39;从AsyncStorage.getItem获取值（＆＃39;值＆＃39;），之后我认为数据存储在AsyncStorage.setItem中（＆＃39; name＆＃39;，＆＃39; value＆＃39; ）。有人看看这段代码并告诉我答案我犯了错误。

export default class AsyncStorageEample extends Component 
{

constructor(props)
{
super(props)

  this.state= { name:'', email:'',mobile:''}
  this.onRegisterPress=this.onRegisterPress.bind(this)
  this.onRetreive=this.onRetreive.bind(this)

}

onRegisterPress()
{
   let name=this.state.name
   let email=this.state.email
   let mobile=this.state.mobile

   AsyncStorage.setItem('name',name)
   AsyncStorage.setItem('email',email)
   AsyncStorage.setItem('mobile',mobile)

   this.setState({name: name, email:email,mobile:mobile})


}

onRetreive()
{
  var user;
  user= AsyncStorage.getItem('name').then((value) => this.setState({ 'name': value }))

  Alert.alert('Name:'+user);
}

render() {
    return (
        <View style={styles.container}>
        <View style={styles.Signupform}>

        <Text style={styles.textStyle}> Name </Text>
        <TextInput style={styles.tInRegister} onChangeText={(text)=>   this.setState({name: text})} value = {this.state.name}/>

        <Text style={styles.textStyle}> Email </Text>
        <TextInput style={styles.tInRegister} onChangeText={(text)=> this.setState({email: text})} value= {this.state.email} />

        <Text style={styles.textStyle}> Mobile </Text>
        <TextInput style={styles.tInRegister} onChangeText={(text)=> this.setState({mobile: text})} vaue= {this.state.mobile} />

        <Button 
         onPress={this.onRegisterPress.bind(this)}
         title="Register"
         color="#841584"
        />

        <Button
        style={styles.get}
        onPress={this.onRetreive.bind(this)}
        title="Get"
        color="#841584"/>
        </View>
        </View>
    );
 }
 }

   const styles = StyleSheet.create({
       container: {
            flex: 1,
            justifyContent: 'center',
            alignItems: 'center',

            backgroundColor: '#F5FCFF',
        },

        tInRegister: {
            fontSize: 16,
            height: 40,
            color: '#800080'
        },
        textStyle: {
            fontSize: 16,
            color: '#800080'
        },
        Signupform: {
            width: 400,
            height: 100,
            justifyContent: 'center',
            marginTop: 10,
            marginLeft: 10,
            marginRight: 10

        },
        get:
        {
          marginTop:20,
        },


});

       AppRegistry.registerComponent('AsyncStorageEample', () =>     AsyncStorageEample);

Answer 1

AsyncStorage是一种异步操作。所以应该用＆＃39;异步 - 等待＆＃39;

尝试以下代码

async onRetreive() {
    const user = await AsyncStorage.getItem('name');
    Alert.alert('Name:'+user);
}

无法使用React native中的AsyncStorage存储和检索数据

1 个答案: