标签：ios开发入门

方法选择器

1` instancesRespondToSelector

SEL sel = @selector(study); if([TRStudent

instancesRespondToSelector:sel] ==

YES)//判定TRStudent类中是否有sel这个实例方法(该语句只能判断实例方法是否存在) {

NSLog(@"类TRStudent中有方法study"); }

2` respondsToSelector

if ([stu respondsToSelector:@selector(learn)] ==YES) {

NSLog(@"对象stu可以调用learn方法"); }

协议选择器

3` conformsToProtocol

TRStudent *stu = [[TRStudent alloc]initWithName:@"张三"

andID:1000]; if ([TRStudent

conformsToProtocol:@protocol(NSCopying)]==YES) { ... }