Converting Localstorage to AsyncStorage in React Native

Question

I have a json object that needs to be stored in local storage/async storage.

This is the local storage code and it compiles on the web correctly.

useEffect(()=>{
    const value = localStorage.getItem(`myData${id}`);
    console.log(value);
    if(value){
        setData(JSON.parse(value));
    }
},[])

useEffect(() => {
    localStorage.setItem(`myData${id}`, JSON.stringify(data));
})

And this is how I converted the same code to AsyncStorage for ios (after importing it)

useEffect(()=>{
    const value = AsyncStorage.getItem(`myData${id}`);
    // console.log(value);
    if(value){
        setData(JSON.parse(value));    //ERROR HERE WITH JSON HIGHLIGHTED IN YELLOW 
    }
},[])

useEffect(() => {
    AsyncStorage.setItem(`myData${id}`, JSON.stringify(data));
})

This shows a render error JSON Parse error: Unexpected identifier "object"

Answer 1

You need to wait for AsyncStorage to get your item data:

     useEffect(()=>{
       const fn = async () => {
         const value = await AsyncStorage.getItem(`myData${id}`);
         if(value){
           setData(JSON.parse(value));    
         }
       }

       fn();
      },[]);

or

     useEffect(()=>{
       AsyncStorage
         .getItem(`myData${id}`)
         .then( value => { 
           if(value){
             setData(JSON.parse(value));    
           }
         });
     },[]);