Objective-C中作为成员变量的字节数组:为什么值不存在?

不能将本地数组分配给要在当前堆栈帧之后保留的指针。你必须使用动态记忆,从 malloc() 或者类似的功能。如果你想使用字节数组,你必须 malloc() memcpy() 和 free() 每次要重新分配内存时,都会正确地分配内存。

- (IBAction) checkNow {
 NSLog(@"now? %d %d %d", theBytes[0], theBytes[1], theBytes[2]);
}

- (void)viewDidLoad {
 [super viewDidLoad];
 uint tryThis[3] = {72,2,244};
 theBytes = malloc(3 * sizeof(uint));
 memcpy(theBytes, tryThis, 3 * sizeof(uint));
 [self checkNow];
}

// In order not to leak, you'll also need:

- (void)dealloc {
  free(theBytes);
  [super dealloc];
}