NSObjct

//
//  main.m
//  Person
//
//  Created by MAC on 15/12/11.
//  Copyright © 2015年 MAC. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "Personn.h"
#import "Stu.h"
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        Class cla = [Personn class];
        Personn *per = [[Personn alloc]init];
        Stu *stu = [[Stu alloc]init];
        id str = @"hell";
        BOOL r = [str isMemberOfClass:cla];  //判断str是否是cla类的实例(不是)
        BOOL r1 = [per isMemberOfClass:cla];  //判断per是否是cla类的实例 (是)  继承关系也不行
         BOOL r2= [stu isMemberOfClass:cla];  //判断per是否是cla类的实例 (不是)  stu继承personn也不行
        NSLog(@"%d%d%d",r,r1,r2); // 0 1 0
        
        
    }
    return 0;
}

#import <Foundation/Foundation.h>
#import "Personn.h"
#import "Stu.h"
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        Class cla = [Personn class];
        Personn *per = [[Personn alloc]init];
        Stu *stu = [[Stu alloc]init];
        id str = @"hell";
        BOOL r = [str isKindOfClass:cla];  //判断str是否是cla类的实例(不是)
        BOOL r1 = [per isKindOfClass:cla];  //判断per是否是cla类的实例 (是)  
         BOOL r2= [stu isKindOfClass:cla];  //判断per是否是cla类的实例 (是)  stu继承personn可以
        NSLog(@"%d%d%d",r,r1,r2); // 0 1 1
判断Stu这个类是否是cla的子类 Stu是类名称 
BOOL r2= [Stu isSubclassOfClass:cla];  

    }
    return 0;
}