我怎样才能使这项工作？我的共享偏好似乎存储了错误的值？

Question

我有这些功能可以设置、删除等我希望全局可用的变量。我担心这可能只是我的一个小错误。我该怎么做才能解决这个问题？

  static setUserId(userId, value) async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.setInt('userId', value);
  }

  static getUserId() async {
    final prefs = await SharedPreferences.getInstance();
    prefs.getInt('userId') ?? 0;
  }

  static removeUserId() async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.remove('userId');
  }

  static removeAllPreferences() async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.clear();
  }
} 



 var userId = user.id;
    var value = userId?.toInt();

    AccountPreferences.setUserId('userId', value);
    var companyId = user.role![0].companyId;

    var test = AccountPreferences.getUserId();

    print(test); ```

When I run the code above all I print out is an instance of Future<dynamic>?
What am I doing wrong?

Answer 1

您还应该在获取值时等待，为此，您应该将函数 getUserId() 声明为 Future 并且 return 函数值如下所示：

  static Future<int> getUserId() async {
    final prefs = await SharedPreferences.getInstance();
    return prefs.getInt('userId') ?? 0;
  }

var test = await AccountPreferences.getUserId(); // await inside here too, where you call it

我怎样才能使这项工作？我的共享偏好似乎存储了错误的值？

How can I make this work? My shared preferences seem to store the wrong value?

sharedpreferences

dart

flutter