如何在当前显示的控制器里判断程序是否被杀死？

通过添加通知：

//1、添加进入后台的判断
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(comeHome:) name:@"UIApplicationDidEnterBackgroundNotification" object:nil];

• (void)comeHome:(UIApplication *)application {
  NSLog(@"进入后台");
  }

//2、添加程序被杀死的判断
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(applicationWillTerminate:) name:@"UIApplicationWillTerminateNotification" object:nil];

• (void)applicationWillTerminate:(UIApplication *)application {
  NSLog(@"程序被杀死");
  }