iOS项目拆分：数据本地持久化(3)

归档是将对象转化为数据字节, 以文件的形式存储在磁盘上，是数据本地持久化方式中的一种。归档数据需要用到Model的时候，创建一个继承与NSObject的类遵循NSCoding协议。

#pragma mark - 单个对象存储
NSArray *array = [NSArray arrayWithObjects:@"X教授",@"金刚狼",@"暴风女", nil]; 
NSString *documentPath =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0]; NSString * filePath = [documentPath stringByAppendingPathComponent:@"saved"];
// 归档 
BOOL result = [NSKeyedArchiver archiveRootObject:array toFile:filePath]; NSLog(@"%d",result); 
// 反归档
NSArray *array1 = [NSKeyedUnarchiver unarchiveObjectWithFile:filePath]; NSLog(@"%@",[array1 objectAtIndex:1]);

#pragma mark - 多个对象存储成一个文档
#pragma mark 第一步：将数据存到data里面
NSMutableData *data = [NSMutableData new];
 // 创建一个工具对象 
NSKeyedArchiver *archivers = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data]; 
[archivers encodeObject:@"X战警" forKey:@"name"]; [archivers encodeObject:@"Movie" forKey:@"type"];
 //标识结束添加
 [archivers finishEncoding];
#pragma mark 将Data存到文件中 
NSString *dataPath = [self documentFilePathWithInfo];
 [data writeToFile:dataPath atomically:YES];
#pragma mark 还是需要借助工具 
//在工具初始化的时候可以绑定一个数据源 
NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc]initForReadingWithData:data]; 
NSString * name = [unarchiver decodeObjectForKey:@"name"];
 NSString * type = [unarchiver decodeObjectForKey:@"type"];
 //标识结束操作
 [unarchiver finishDecoding];