NSUserDefaults standardUserDefaults 存储和读取

NSUserDefaults 

简介：NSUserDefaults用来存储数据量小的数据。支持：NSString/NSData/NSArray/NSNumber/NSDictionary

使用：

//创建
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
//存储 forKey：唯一标识
[defaults setObject:config forKey:Key];

//同步
[defaults synchronize];

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSMutableDictionary *config = [NSMutableDictionary dictionaryWithDictionary:[defaults objectForKey:Key]];
//config = [[NSUserDefaults standardUserDefaults] objectForKey:Key];