- (void)viewDidLoad {
    [super viewDidLoad];
    NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
    NSString *libraryPath = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) lastObject];
    NSFileManager *fileMgr = [NSFileManager defaultManager];
      NSError *error = nil;
    //删除test02里的文件
    NSString *dirPath = [documentsPath stringByAppendingPathComponent:@"test02"];
  
    for(int j = 0; j < 5; j++)
    {
        NSString *filePath = [dirPath stringByAppendingPathComponent:[NSString stringWithFormat:@"test%02d.txt",j+1]];

        [fileMgr removeItemAtPath:filePath error:&error];
    }
    
    
    //将document/test01移动到library/Cache
    NSString *sourcePath = [documentsPath stringByAppendingPathComponent:@"test01"];
    NSString *targetPath = [libraryPath stringByAppendingPathComponent:@"Caches/test01"];
    [fileMgr moveItemAtPath:sourcePath toPath:targetPath error:&error];

//创建两个文件夹和5个文件
    for(int i = 0; i < 2; i++)
    {
    NSString *DirPath = [documentsPath stringByAppendingPathComponent:[NSString stringWithFormat:@"test%02d",i+1]];
        NSError *error = nil;
        [fileMgr createDirectoryAtPath:DirPath withIntermediateDirectories:YES attributes:nil  error:&error];
        
        for(int j = 0; j < 5; j++)
        {
          NSString *filePath = [DirPath stringByAppendingPathComponent:[NSString stringWithFormat:@"test%02d.txt",j+1]];
            NSString *fileContent = [NSString stringWithFormat:@"this number of file is %02d",j+1];
            [fileMgr createFileAtPath:filePath contents:[fileContent dataUsingEncoding:NSUTF8StringEncoding] attributes:nil];
        }
    }
}