NSFileManager文件管理
Bundles and Packages
bundle和package是两种不同的概念,官方概念:
A package is any directory that the Finder presents to the user as if it were a single file.
A bundle is a directory with a standardized hierarchical structure that holds executable code and the resources used by that code.
翻译过来就是,包是Finder像一个文件一样呈现给用户的目录。而bundle是一个容纳了可执行代码以及代码使用的资源文件的标准体系结构的目录。
Finder把满足一下条件的目录当作包:
The directory has a known filename extension: .app
, .bundle
, .framework
, .plugin
, .kext
, and so on.
The directory has an extension that some other application claims represents a package type;
The directory has its package bit set.
打开Finder -> 应用程序 ->日历 -> 右键,我们可以看到显示包内容,这个名为日历的文件就是一个包。
文件管理
检查文件是否存在:
NSFileManager *fileManager = [NSFileManager defaultManager]; NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject]; NSString *filePath = [documentsPath stringByAppendingPathComponent:@"file.txt"]; BOOL fileExists = [fileManager fileExistsAtPath:filePath];
列出目录里的文件/目录:
方法一:
NSString *path = [NSBundle mainBundle].bundlePath; NSFileManager *fileManager = [NSFileManager defaultManager]; NSArray *arr = [fileManager contentsOfDirectoryAtPath:path error:nil]; for (NSString *string in arr) { NSLog(@"%@",string); }
方法二:
NSURL *url = [NSBundle mainBundle].bundleURL; NSFileManager *fileManager = [NSFileManager defaultManager]; NSArray *arr = [fileManager contentsOfDirectoryAtURL:url includingPropertiesForKeys:nil options:NSDirectoryEnumerationSkipsHiddenFiles error:nil]; for (NSString *string in arr) { NSLog(@"%@",string); }
在目录中递归地遍历文件:
NSFileManager *fileManager = [NSFileManager defaultManager]; NSURL *bundleURL = [[NSBundle mainBundle] bundleURL]; NSDirectoryEnumerator *enumerator = [fileManager enumeratorAtURL:bundleURL includingPropertiesForKeys:@[NSURLNameKey, NSURLIsDirectoryKey] options:NSDirectoryEnumerationSkipsHiddenFiles errorHandler:^BOOL(NSURL *url, NSError *error) { if (error) { NSLog(@"[Error] %@ (%@)", error, url); return NO; } return YES; }]; NSMutableArray *mutableFileURLs = [NSMutableArray array]; for (NSURL *fileURL in enumerator) { NSString *filename; [fileURL getResourceValue:&filename forKey:NSURLNameKey error:nil]; NSNumber *isDirectory; [fileURL getResourceValue:&isDirectory forKey:NSURLIsDirectoryKey error:nil]; // Skip directories with '_' prefix, for example if ([filename hasPrefix:@"_"] && [isDirectory boolValue]) { [enumerator skipDescendants]; continue; } if (![isDirectory boolValue]) { [mutableFileURLs addObject:fileURL]; } }
创建一个目录:
NSFileManager *fileManager = [NSFileManager defaultManager]; NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject]; NSString *imagesPath = [documentsPath stringByAppendingPathComponent:@"images"]; if (![fileManager fileExistsAtPath:imagesPath]) { [fileManager createDirectoryAtPath:imagesPath withIntermediateDirectories:NO attributes:nil error:nil]; }
删除一个文件或者目录:
NSFileManager *fileManager = [NSFileManager defaultManager]; NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject]; NSString *filePath = [documentsPath stringByAppendingPathComponent:@"image.png"]; NSError *error = nil; if (![fileManager removeItemAtPath:filePath error:&error]) { NSLog(@"[Error] %@ (%@)", error, filePath); }
获取文件的创建日期:
NSFileManager *fileManager = [NSFileManager defaultManager]; NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject]; NSString *filePath = [documentsPath stringByAppendingPathComponent:@"Document.pages"]; NSDate *creationDate = nil; if ([fileManager fileExistsAtPath:filePath]) { NSDictionary *attributes = [fileManager attributesOfItemAtPath:filePath error:nil]; creationDate = attributes[NSFileCreationDate]; }
完