按书上的例子敲了敲：
#import <Foundation/Foundation.h>
int main(int argc,const char *argv[]){
@autoreleasepool {
//声明文件管理对象
NSFileManager *manager;
//由defaultManager方法创建NSFileManager初始化
manager = [NSFileManager defaultManager];
//声明要遍历路径
NSString *home;
//初始化要遍历的目录:用户根目录
home = [@"~" stringByExpandingTildeInPath];
//声明文件遍历对象
NSDirectoryEnumerator *direnum;
//初始化文件遍历对象,用文件目录对象home作参
direnum = [manager enumeratorAtPath:home];
//可变列表来保存遍历的文件
NSMutableArray *files;
//初始化大小设置为42
files = [NSMutableArray arrayWithCapacity:42];
//枚举迭代的对象
NSString *filename;
//使用迭代对象的方法来逐个遍历枚举中的所有元素
while(filename =[direnum nextObject]){
//判断文件是否是jpg格式的文件
if([[filename pathExtension] isEqualTo:@"jpg"]){
//将文件名添加到列表中
[files addObject:filename];
}
}
//声明文件列表枚举
NSEnumerator *fileenum;
//初始化枚举对象
fileenum = [files objectEnumerator];
//枚举遍历所有元素
while (filename=[fileenum nextObject]) {
//打印信息
NSLog(@"%@",filename);
}
};//autoreleasepool
return 0;
}//main
输出
2015-01-27 23:00:11.181 04.01 Shapes-Inheritance[449:9009] Desktop/psb.jpg
2015-01-27 23:00:11.194 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/QPR/15.jpg
2015-01-27 23:00:11.194 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/QPR/19.jpg
2015-01-27 23:00:11.194 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/QPR/22.jpg
2015-01-27 23:00:11.195 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/QPR/24.jpg
2015-01-27 23:00:11.195 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/QPR/4.jpg
2015-01-27 23:00:11.195 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/QPR/QPR.numbers/preview-micro.jpg
2015-01-27 23:00:11.195 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/QPR/QPR.numbers/preview-web.jpg
2015-01-27 23:00:11.196 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/QPR/QPR.numbers/preview.jpg
2015-01-27 23:00:11.196 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/伯恩利/11.jpg
2015-01-27 23:00:11.196 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/伯恩利/21.jpg
2015-01-27 23:00:11.196 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/伯恩利/7.jpg
2015-01-27 23:00:11.215 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/伯恩利/Burnley.numbers/preview-micro.jpg
2015-01-27 23:00:11.215 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/伯恩利/Burnley.numbers/preview-web.jpg
2015-01-27 23:00:11.215 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/伯恩利/Burnley.numbers/preview.jpg
2015-01-27 23:00:11.216 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/切尔西/10.jpg
2015-01-27 23:00:11.216 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/切尔西/14.jpg
2015-01-27 23:00:11.216 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/切尔西/19.jpg
2015-01-27 23:00:11.217 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/切尔西/2.jpg
2015-01-27 23:00:11.217 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/切尔西/21.jpg
2015-01-27 23:00:11.217 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/切尔西/4.jpg
2015-01-27 23:00:11.218 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/切尔西/7.jpg
2015-01-27 23:00:11.218 04.01 Shapes-Inheritance[449:9009] Documents/aodci/球员信息/切尔西/chelsea.numbers/preview-micro.jpg