1.NSFileManager：单例,对文件进行操作
[NSFileManager defaultManager]
2.UIImage转NSData
NSData *imageData = UIImagePNGRepresentation(image);
3.NSHomeDirectory:获取应用的主路径
NSString *path = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents/pic"];
4.fileExistsAtPath判断路径下是否存在这个文件
BOOL isExit = [[NSFileManager defaultManager] fileExistsAtPath:path];
5.createFileAtPath:在路径上创建文件
[[NSFileManager defaultManager] createFileAtPath:path contents:nil attributes:nil];
6.createDirectoryAtPath：在路径上创建目录
[[NSFileManager defaultManager] createDirectoryAtPath:dir2Path withIntermediateDirectories:YES attributes:nil error:nil];
7.将文件转化为NSData
NSData *data = [NSData dataWithContentsOfFile:path];
8.获得应用的Document目录
NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
9.moveItemAtPath:toPath:将第一个路径上的文件移动到另一个路径
[[NSFileManager defaultManager] moveItemAtPath:path toPath:[dir1Path stringByAppendingPathComponent:@"pic1"] error:&errorMsg];
10.copyItemAtPath:toPath:将第一个路径上的文件拷贝粘贴到另一个路径上
[[NSFileManager defaultManager] copyItemAtPath:[dir1Path stringByAppendingPathComponent:@"pic1"] toPath:[dir2Path stringByAppendingPathComponent:@"pic2"] error:&errorMsg];
11.removeItemAtPath:删除文件
[[NSFileManager defaultManager] removeItemAtPath:dir1Path error:nil];
小例子：
@interface ViewController ()@property (nonatomic, strong) NSFileManager *fileManager;@end///Users/a/Library/Developer/CoreSimulator/Devices/4DF9F8F0-E0BD-4EFC-AC49-340DAE285D62/data/Containers/Data/Application/77EA378C-8B16-424E-8607-456EAC48EC7A/Documents/pic@implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; //获取系统提供文件管理器 单例 self.fileManager = [NSFileManager defaultManager]; //读取图片 UIImage *image = [UIImage imageNamed:@"4.jpg"]; //UIImage -> NSData//二进制 NSData *imageData = UIImagePNGRepresentation(image);// NSLog(@"%@", imageData); //创建文件 NSString *path = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents/pic"];//添加的是路径的一部分 NSLog(@"%@", path); //创建文件 if (![self.fileManager fileExistsAtPath:path]) { //文件不存在 //创建一个空的文件 [self.fileManager createFileAtPath:path contents:nil attributes:nil]; //写入内容 [imageData writeToFile:path atomically:YES]; } //读取文件 if ([self.fileManager fileExistsAtPath:path]) { NSData *data = [NSData dataWithContentsOfFile:path]; UIImage *image = [UIImage imageWithData:data]; self.view.backgroundColor = [UIColor colorWithPatternImage:image]; } //创建两个目录:目录1 目录2 NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];//自动寻找可操作的目录，但是只有一个// NSLog(@"%@", dir1Path); //两个方法不同 NSString *dir1Path = [docPath stringByAppendingString:@"/目录1"]; NSString *dir2Path = [docPath stringByAppendingPathComponent:@"目录2"];// NSLog(@"%@, %@", dir1Path, dir2Path); // BOOL *isExist; if (![self.fileManager fileExistsAtPath:dir1Path]) { //不存在，创建 [self.fileManager createDirectoryAtPath:dir1Path withIntermediateDirectories:YES attributes:nil error:nil]; } if (![self.fileManager fileExistsAtPath:dir2Path]) { //不存在，创建 [self.fileManager createDirectoryAtPath:dir2Path withIntermediateDirectories:YES attributes:nil error:nil]; } //将Documents/pic 移动到Documents/目录1/pic1,移动的时候还要设置文件名 NSError *errorMsg = NULL; [self.fileManager moveItemAtPath:path toPath:[dir1Path stringByAppendingPathComponent:@"pic1"] error:&errorMsg]; if (errorMsg) { //有错误信息 NSLog(@"errorMsg:%@", errorMsg); }else{ NSLog(@"move ok"); } //将目录1/pic1 拷贝copy 到目录2/pic1 [self.fileManager copyItemAtPath:[dir1Path stringByAppendingPathComponent:@"pic1"] toPath:[dir2Path stringByAppendingPathComponent:@"pic2"] error:&errorMsg]; if (errorMsg) { //有错误信息 NSLog(@"errorMsg:%@", errorMsg); }else{ NSLog(@"copy ok"); } //删除文件 [self.fileManager removeItemAtPath:dir1Path error:nil];}@end