class反射
通过类名的字符串形式实例化对象
Class class NSClassFromString@(@"student");
Student *stu = [[class alloc] init];
将类名变为字符串
Class class = [student class];
NSString *className = NSStringFromClass(class);
SEL的反射
通过方法的字符串形式实例化对象
SEL selector = NSSelectorFromClass(@"setName");
[stu performSelector:selector withObject:@"Mike"];
将方法变为字符串
NSStringFromSelector(@selector*(setName:));
