NSString 截取，文件读取【转】
【转】http://www.cnblogs.com/csj007523/archive/2012/07/15/2592302.html
小结：
1）componentsSeparatedByString:截取指定字符串；
2) pathForResource：获取程序运行时目录
3) objectAtIndex:获取当前索引的字符串；
4) rangeOfString:获取指定短字符串在长字符串中的开始，结尾索引值；
5) stringWithContentsOfFile：按行读取文件
6) componentsSeparatedByString:@"\n"];换行分割字符串；
7) NSEnumerator *nse = [lines objectEnumerator];将数组转换为NSEnumerator，可向前读取数据；
8) nextObject：读取下一行数据；
-(void) splitString{NSString *animals = @"dog#cat#pig";//将#分隔的字符串转换成数组NSArray *array = [animals componentsSeparatedByString:@"#"];NSLog(@"animals:%@",array);//获取程序运行时目录NSString *escapedPath = [[NSBundle mainBundle] pathForResource:@"info" ofType:@"plist"];NSArray *strings = [escapedPath componentsSeparatedByString: @"/"];NSString *tmpFilename = [strings objectAtIndex:[strings count]-1];NSRange iStart = [escapedPath rangeOfString : tmpFilename];NSString *runtimeDirectory = [escapedPath substringToIndex:iStart.location-1];NSLog(@"runtimeDirectory:%@",runtimeDirectory);//按行读取文件NSString *tmp;NSArray *lines = [[NSString stringWithContentsOfFile:@"test.txt" encoding:nil error:nil] componentsSeparatedByString:@"\n"];NSEnumerator *nse = [lines objectEnumerator];while(tmp = [nse nextObject]) {NSLog(@"tmp:%@", tmp);}}