iphone上的数据存储有四种模式：
Property lists 属性列表
Object archives (or archiving) 对象归档
SQLite3 (iOS’s embedded relational database)
Core Data (Apple’s provided persistence tool)
存储中经常需要提取两个相关的目录路径：Documents和tmp
Getting the Documents Directory ：
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filename = [documentsDirectory stringByAppendingPathComponent:@"theFile.txt"];
Getting the tmp Directory ：
NSString *tempPath = NSTemporaryDirectory();
NSString *tempFile = [tempPath stringByAppendingPathComponent:@"tempFile.txt"];
文件存储分为单文件存储和多文件存储（Single-File Persistence 、Multiple-File Persistence ）
本文转自老Zhan博客园博客，原文链接http://www.cnblogs.com/mybkn/archive/2012/03/27/2418971.html，如需转载请自行联系原作者
