How to create directory file wrapper
//ファイルラッパの作成
NSFileWrapper *wrapper = [[[NSFileWrapper alloc] initDirectoryWithFileWrappers:NULL ] autorelease];
//データを追加する
[wrapper addFileWrapper:aWrapper ];
[wrapper addFileWrapper:anotherWrapper ];
[wrapper addRegularFileWithContents:aData preferredFilename:@"aData"];
How to decode file wrapper
NSDictionary* aDic = [wrapper fileWrappers];
NSFileWrapper* aWrapper;
NSFileWrapper* anotherWrapper;
aWrapper = [aDic objectForKey:@"aWrapper's name.rtfd"];
anotherWrapper = [aDic objectForKey:@"anotherWrapper's name.rtfd"];
data1 = [aWrapper serializedRepresentation];
data2 = [anotherWrapper serializedRepresentation];
data3 = [[aDic objectForKey:@"aData"] regularFileContents];