Apple开发_NSString 使用 strong 与 copy 进行修饰的区别

• 测试代码

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    
    NSMutableString *m_notiion = [[NSMutableString alloc] init];
    m_notiion.string = @"房号密码的功能";
    self.m_notiion = m_notiion;
    [m_notiion appendString:@"加点文字"];

    CHLog(@"UIApplication == %@", self.m_notiion);
}

• 使用 strong 修饰

  @interface GC_AppDelegate ()
  
  @property(nonatomic, strong) NSString *m_notiion;
  
  @end
  

  • 结果
    

• 使用 copy 修饰

  @interface GC_AppDelegate ()
  
  @property(nonatomic, copy) NSString *m_notiion;
  
  @end
  

  • 结果