iOS开发中的归解档

首先要遵守NSCoding协议;
重写两个方法:

//归档属性
- (void)encodeWithCoder:(NSCoder *)coder
{
    //归档!!
    unsigned int count = 0;
    Ivar * ivars = class_copyIvarList([self class], &count);
    for (int i = 0; i < count; i++) {
        Ivar ivar = ivars[i];
        //属性名
        const char * name = ivar_getName(ivar);
        NSString * KEY = [NSString stringWithUTF8String:name];
        //KVC
        id value = [self valueForKey:KEY];
        //归档
        [coder encodeObject:value forKey:KEY];
    }
    //但凡在C语言里面 看到New Creat Copy 都需要释放
    free(ivars);
    
}
//解档
- (instancetype)initWithCoder:(NSCoder *)coder
{
    self = [super init];
    if (self) {
        unsigned int count = 0;
        Ivar * ivars = class_copyIvarList([self class], &count);
        for (int i = 0; i < count; i++) {
            //名称
            const char * name = ivar_getName(ivars[i]);
            NSString * KEY = [NSString stringWithUTF8String:name];
            //解档
            id value = [coder decodeObjectForKey:KEY];
            //设置到成员变量上
            [self setValue:value forKey:KEY];
        }
    free(ivars);
        
    }
    return self;
}