简单数据存储

只能用于基本数据类型： int、double、bool、string 和 stringList。

dependencies:
  flutter:
    sdk: flutter
  shared_preferences: 
  
  
  
final prefs = await SharedPreferences.getInstance();

// set value
prefs.setInt('counter', counter);

final prefs = await SharedPreferences.getInstance();

// Try reading data from the counter key. If it doesn't exist, return 0.
final counter = prefs.getInt('counter') ?? 0;

final prefs = await SharedPreferences.getInstance();

prefs.remove('counter');