归档小结，归档时iOS 数据存储方式之一，可以用来存储自定义数据模型。

归档有两个主要的API：

第一种：NSKeyedArchiver的实例方法

NSMutableData *data = [[NSMutableData alloc] init];

    NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data];

    [archiver encodeObject:student forKey:kData];

    [archiver finishEncoding];

    [data writeToFile:[self getFilePath] atomically:YES];

其二： NSKeyedArchiver的类方法

NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];

    NSString *path = [docPath stringByAppendingPathComponent:@"address.plist"];

    [NSKeyedArchiver archiveRootObject:model toFile:path];