我有以下代码用于从iphone的文档目录中获取文件:NSString*docsDir;NSString*realpath;NSArray*dirPaths;dirPaths=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES);docsDir=dirPaths[0];realpath=[[NSStringalloc]initWithString:[docsDirstringByAppendingPathComponent:@"2_program.db"]];NSFileManager*