偏好設(shè)置-實(shí)例代碼:

// 存數(shù)據(jù)
- (IBAction)save:(id)sender { 
  // 偏好設(shè)置NSUserDefaults 
  // 底層就是封閉了?個(gè)字典,利?字典的?式生成plist?件
  // 好處:不需要關(guān)?文件名(它會(huì)自動(dòng)生成)快速進(jìn)?鍵值對(duì)存儲(chǔ).
  NSUserDefaults *defautls = [NSUserDefaultsstandardUserDefaults];
  [defautls setObject:@"gaowei" forKey:@"name"];
  [defautls setBool:YES forKey:@"isBool"]; 
  [defautls setInteger:5 forKey:@"num"]; 
  //同步,?即寫入文件.
  [defautls synchronize];
}

// 讀數(shù)據(jù)
- (IBAction)reader:(id)sender {
  // 存是?什么key存的, 讀的時(shí)候就要用什么key值取 
  // 存的時(shí)候使?的什么類型,取的時(shí)候也要用什么類型.
  NSString *str = [[NSUserDefaults standardUserDefaults] objectForKey:@"name"];
  BOOL isBool = [[NSUserDefaultsstandardUserDefaults] boolForKey:@"isBool"];
  NSInteger num = [[NSUserDefaults standardUserDefaults] integerForKey:@"num"];
  NSLog(@"name =%@-isBool=%d-num=%ld",str,isBool,num);
}

歸檔-實(shí)例代碼:

// 保存數(shù)據(jù)
- (IBAction)save:(id)sender {
  // 歸檔?般都是保存自定義對(duì)象的時(shí)候,使用歸檔.因?yàn)閜list文件不能夠保存自定義對(duì)象. 
  // 如果一個(gè)字典當(dāng)中保存有自定義對(duì)象,如果把這個(gè)字典寫?到文件當(dāng)中,它是不會(huì)?成plist?件的.
  Persion *persion = [[Persion alloc] init];
  persion.name = @"gaowei"; 
  persion.age = 18;
  // 獲取沙盒臨時(shí)目錄
  NSString *tempPath = NSTemporaryDirectory(); 
  NSString *filePath = [tempPath stringByAppendingPathComponent:@"persion.data"]; 
  // archiveRootObject這個(gè)?法底層會(huì)去調(diào)用保存對(duì)象的encodeWithCoder?法,去詢問要保存這個(gè)對(duì)象的哪些屬性.
  // 所以要實(shí)現(xiàn)encodeWithCoder方法, 告訴要保存這個(gè)對(duì)象的哪些屬性.
  [NSKeyedArchiver archiveRootObject:persion toFile:filePath]; 
}

// 讀取數(shù)據(jù)
- (IBAction)reader:(id)sender { 
  // 獲取沙盒臨時(shí)目錄
  NSString *tempPath = NSTemporaryDirectory(); 
  NSString *filePath = [tempPath stringByAppendingPathComponent:@"persion.data"]; 

  // NSKeyedUnarchiver會(huì)調(diào)?initWithCoder這個(gè)?法,來讓你告訴它去獲取這個(gè)對(duì)象的哪些屬性. 
  // 所以我們?cè)诒４娴膶?duì)象當(dāng)中實(shí)現(xiàn)initWithCoder?法. 
  Persion *persion = [NSKeyedUnarchiver unarchiveObjectWithFile:filePath];
  NSLog(@"name=%@---age=%d",persion.name,persion.age);
}

要保存的對(duì)象

#import <Foundation/Foundation.h> 
 // 要遵守<NSCoding>協(xié)議
@interface Persion : NSObject <NSCoding>
@property (nonatomic, strong) NSString *name;
@property(nonatomic, assign) int age;
@end

 // archiveRootObject這個(gè)方法底層會(huì)去調(diào)用保存對(duì)象的encodeWithCoder?法,去詢問要保存這個(gè)對(duì)象的哪些屬性. 
 // 只有遵守了NSCoding協(xié)議之后才能夠?qū)崿F(xiàn)這個(gè)方法. 
-(void)encodeWithCoder:(NSCoder *)encode {
    [encode encodeObject:self.name forKey:@"name"];
    [encode encodeInt32:self.age forKey:@"age"];
}
 
// NSKeyedUnarchiver會(huì)調(diào)用initWithCoder這個(gè)方法,來讓你告訴它去獲取這個(gè)對(duì)象的哪些屬性.
 // initWithCoder什么時(shí)候調(diào)用:解析一個(gè)文件的時(shí)候就會(huì)調(diào)用. 
-(instancetype)initWithCoder:(NSCoder *)decoder {
  // 這個(gè)地?為什么沒有[super initWithCoder]
  // 是因?yàn)樗母割悰]有遵守NSCoding協(xié)議
  if (self = [super init]) {
      // 要給它??的屬性進(jìn)行賦值,外界取得對(duì)象時(shí)訪問該屬性,里?才會(huì)用值. 
      self.age = [decoder decodeInt32ForKey:@"age"];
      self.name = [decoder decodeObjectForKey:@"name"];
   }
    return self;
}