////////////////////    .h    /////////////////////

#import <Foundation/Foundation.h>

@protocol StudentProtocol <NSObject>

@optional   //下面的方法是可选实现的

- (void)fallInLove:(NSString *)name;

@required  //下面的方法是必须实现的

- (void)curriculum;

@end

////////////////    .h    ///////////////////

#import "Person.h"

#import "StudentProtocol.h"

@interface Student : Person <StudentProtocol>

- (id)initWithName:(NSString *)name sex:(NSString *)sex age:(int)age;

@end

////////////////    .m   ///////////////////

#import "Student.h"

@implementation Student

- (id)initWithName:(NSString *)name sex:(NSString *)sex age:(int)age

{

    self = [super init];

    if (self) {

        self.name = name;

        self.sex = sex;

        self.age = age;

    }

    return self;

}

- (Person *)work

{

    NSLog(@"%@正在工作",self.name);

    return 0;

}

- (void)printInfo {

    NSLog(@"我的名字叫：%@ 今年%d岁 我是一名%@ %@",self.name,self.age,self.sex,NSStringFromClass([self class]));

}

#pragma mark StudentProtocol

- (void)fallInLove:(NSString *)name {

    NSLog(@"我还是学生,谈不谈恋爱都可以...但是我还是在和 ---> %@ <--- 谈恋爱"，name);

}

- (void)curriculum {

    NSLog(@"我是学生，必须上课学习...");

}

@end

#import "AppDelegate.h"

#import "Student.h"

#import "StudentProtocol.h"

@interface AppDelegate ()

@end

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    Student *s = [[Student alloc] initWithName:@"小明" sex:@"男" age:12];

    if ([s conformsToProtocol:@protocol(StudentProtocol)]) {　　//判断是否遵循了某个协议

        NSLog(@"我遵循了 --- StudentProtocol --- 协议");

        if ([s respondsToSelector:@selector(fallInLove:)]) {　　//判断是否有实现某个方法

            [s fallInLove:@"如花"];

        }

    }

    return YES;

}

@end