iOS保存model数据（自定义Model 可以存放到本地）

1.先创建类目类：继承于NSUserDefaults

2其次前提：保存的model要实现NSCoding

3.在自定义的类目实现这两个方法

-(void)setCustomObj:(id)obj forKey:(NSString *)key;

-(id)customObjForKey:(NSString *)key;

在自定义的类目中实现这两个方法

-(void)setCustomObj:(id)obj forKey:(NSString *)key

{

    if ([obj respondsToSelector:@selector(encodeWithCoder:)] == NO) {

        NSLog(@"对象存入失败！对象必须实现NSCoding 协议的 encodeWithCoder:方法");

        return;

    }

    NSData * encodeObject = [NSKeyedArchiver archivedDataWithRootObject:obj];

    NSUserDefaults * defaults = [NSUserDefaults standardUserDefaults];

    [defaults setObject:encodeObject forKey:key];

    [defaults synchronize];

}

 -(id)customObjForKey:(NSString *)key

{

    NSUserDefaults * defaults = [NSUserDefaults standardUserDefaults];

    NSData * encodeObject = [defaults objectForKey:key];

    if (encodeObject == nil) {

        return nil;

    }

    id obj = [NSKeyedUnarchiver unarchiveObjectWithData:encodeObject];

    return obj;

}

4.再次来到我们保存model中实现NSCoding协议

- (id)initWithCoder:(NSCoder *)decoder

{

    self = [super initWithCoder:decoder];

    

    if (self) {

        self.cityId = [decoder decodeObjectForKey:@"cityId"];

        self.cityName = [decoder decodeObjectForKey:@"cityName"];

        self.cityLat = [decoder decodeObjectForKey:@"cityLat"];

        self.cityLng = [decoder decodeObjectForKey:@"cityLng"];

        self.firstCharacter = [decoder decodeObjectForKey:@"firstCharacter"];

        self.subsidiaryBankId = [decoder decodeObjectForKey:@"subsidiaryBankId"];

    }

    

    return self;

}

 

- (void)encodeWithCoder:(NSCoder *)aCoder

{

    [aCoder encodeObject:self.cityId forKey:@"cityId"];

    [aCoder encodeObject:self.cityName forKey:@"cityName"];

    [aCoder encodeObject:self.cityLat forKey:@"cityLat"];

    [aCoder encodeObject:self.cityLng forKey:@"cityLng"];

    [aCoder encodeObject:self.firstCharacter forKey:@"firstCharacter"];

    [aCoder encodeObject:self.subsidiaryBankId forKey:@"subsidiaryBankId"];

 

}

 5.最后来到控制器中，实例化类目，就可以实现保存model