AsyncStorage 问题：尽管布尔值正确，但“if”语句内的代码并未执行

Question

我正在尝试从 expo-async-storage 读取数据，将数据设置为变量并检查它是否包含 searchString。

首先，我获取当前的 MovieID

useEffect(() => { 
const fetchMovieID = async () => { 
  try { 
    const fetchedID = await item.id; 
    setMovieID(fetchedID);
  } catch (error) { 
    console.error("Error fetching movie ID:", error);
  }
};
fetchMovieID();
}, [item]);

然后我创建第二个 useEffect

useEffect(() => {
setLoading(true);
getMovieDetails(item.id);
getMovieCredits(item.id);
getSimilarMovies(item.id);

if (movieID !== "") {
  getData("Movies");
}
}, [item, movieID]);

const getData = async (key) => {
try {
  const value = await AsyncStorage.getItem(key);
  if (value !== null) {
    console.log("Readed value:", value);
    const isAlreadyAdded = favouriteMovies.includes(movieID);
    console.log("Finding status:", isAlreadyAdded);
    

    if (!isAlreadyAdded) {
      setFavouriteMovies((prevMovies) => [...prevMovies, movieID]);
    } else {
      console.log("Cant find");
      console.log("Movie ID", movieID);
    }
  }
} catch (e) {
  console.log("Error reading data:", e);
}
};

问题在于，即使 isAlreadyAdded 变量正确设置为 false，'if' 中的代码也不会执行。

来自控制台的日志：

 LOG  Readed value: 1139829 LOG  Finding status: false

我尝试创建另一个异步函数并等待分配布尔变量。 当然，无需分配布尔变量。

Answer 1

我自己想出来的。 首先，我创建了一个包含所有异步存储常量函数的新文件：

import AsyncStorage from "@react-native-async-storage/async-storage";

const getAllKeys = async () => {
    let keys = []
    try {
      keys = await AsyncStorage.getAllKeys()
    } catch(e) {
        console.log('Get all keys error: ', e)
    }
    return keys
  }


  const setObjectItem = async (key, value) => {
    try {
      const jsonValue = JSON.stringify(value)
      await AsyncStorage.setItem(key, jsonValue)
    } catch(e) {
        cconsole.log('Error wthile saving object: ', e)
    }
  
    console.log('Properly saved: ', value)
  }

  const getObjectItem = async (key) => {
    try {
      const jsonValue = await AsyncStorage.getItem(key)
      return jsonValue != null ? JSON.parse(jsonValue) : null
    } catch(e) {
        console.log('Error while getting object: ', e)
    }
    console.log('Object successfully readed')
  }

  export default {
    getAllKeys,
    setObjectItem,
    getObjectItem,
  }

然后，在另一个屏幕上，我从 API 获取我的 movieID：

import AsyncStorageOperations from "../src/components/AsyncStorageOperations";

    const [movieID, setMovieID] = useState("");
    
    useEffect(() => {
        const fetchMovieID = async () => {
          try {
            const fetchedID = await item.id;
            setMovieID(fetchedID);
          } catch (error) {
            console.error("Error fetching movie ID:", error);
          }
        };
        fetchMovieID();
      }, [item]);

在另一个 useEffect 中，我正在执行 checkMoviesStorage() 函数：

useEffect(() => {
    (..)
    checkMoviesStorage();
    (..)
  }, [item, movieID]);

  const checkMoviesStorage = async () => {
    if (movieID !== "") {
      if ((await AsyncStorageOperations.getAllKeys().length) !== 0) {
        console.log("KeysArray is not empty");
        emptyKeysArray = false;
        movieKeys = await AsyncStorageOperations.getStringValue("movie");
        console.log(movieKeys, movieID);

        if (movieKeys.includes(movieID)) {
          console.log("Incredible, found!");
        } else {
          console.log("Nothing");
        }
      } else {
        console.log("KeysArray is empty");
        emptyKeysArray = true;
        console.log(emptyKeysArray);
      }
    }
  };

在按“添加到收藏夹”后调用的函数中，我更改图标的颜色，设置小吃栏并在满足条件时添加到收藏夹：

function manageFavourites() {
    setSnackbarVisile(!snackbarVisible);
    toggleFavourite(!isFavourite);

    if (isFavourite) {
      console.log("Deleting from favourites");
      setSnackbarText("Deleting from favourites");
    } else {
      console.log("Adding to favourites");
      setSnackbarText("Adding to favourites");
      AsyncStorageOperations.setObjectItem("movie", movieID);
    }
  }