一 ：简单例子

1.让类实现NSCopying/NSMutableCopying协议。

2.让类实现copyWithZone:/mutableCopyWithZone:方法

@interface Person : NSObject(NSCopying)(因识别问题此处圆括号替换尖括号)
@property (nonatomic, assign) NSInteger age;
@property (nonatomic, copy) NSString *name;
@end
import "Person.h"
 
@implementation Person

- (id)copyWithZone:(NSZone *)zone {
 
    Person *person = [[[self class] allocWithZone:zone] init];
    person.age = self.age;
    person.name = self.name;//这里的self就是copy的对象
 
    return person;
}

- (id)mutableCopyWithZone:(NSZone *)zone  
{  
         Person *person = NSCopyObject(self, 0, zone);  
        person.age = self.age;
    person.name = self.name;//这里的self就是copy的对象
         return person;  
}  

必须遵守NSCopying，NSMutableCopying协议，不然当Person对象执行copy和mutableCopy时会崩溃！

二 ：BaseCopyObject:

#import "BaseCopyObject.h"

@implementation BaseCopyObject

- (id)copyWithZone:(NSZone *)zone{
    BaseCopyObject *baseObject = [[self class] allocWithZone:zone];
    [self copyOperationWithObject:baseObject];
    return baseObject;
}
//子类来主宰赋值操作   重写父类的方法
- (void)copyOperationWithObject:(id)object{
    
}
@end

#import “Person.h"
@implementation Tools
- (void)copyOperationWithObject:(Person *)object{
    object.age = self.age;
}
- (NSString *)description{
    return [NSString stringWithFormat:@"<%@ :%p\"age:%ld\">",self.class,self,_age];
}