优先导入头文件

import <objc/runtime.h>

- (void)encodeWithCoder:(NSCoder *)aCoder {
    unsigned int count = 0;
    Ivar *ivars = class_copyIvarList([self class], &count);
    for (int i = 0; i < count; i++) {
        Ivar ivar = ivars[i];
        const char *name = ivar_getName(ivar);
        NSString *key = [NSString stringWithUTF8String:name];
        //归档
        [aCoder encodeObject:[self valueForKey:key] forKey:key];
    }
    free(ivars);
}


- (instancetype)initWithCoder:(NSCoder *)aDecoder {
    if (self = [super init]) {
        unsigned int count = 0;
        Ivar *ivars = class_copyIvarList([self class], &count);
        for (int i = 0; i < count; i++) {
            Ivar ivar = ivars[i];
            const char *name = ivar_getName(ivar);
            NSString *key = [NSString stringWithUTF8String:name];
            //反归档
            id value = [aDecoder decodeObjectForKey:key];
            //设置到成员变量身上
            [self setValue:value forKey:key];
            
        }
        free(ivars);
    }
    return self;
}