iOS: How do you find the creation date of a file?

问题

I'm trying to find the creation date (NOT modification date) of a file.

Creation date doesn't appear to be in the attributes of a file, though modified date is.

I'm using this code..

NSFileManager* fm = [NSFileManager defaultManager];

NSString* path = [PathHelpers pathInDocumentsFolderWithFilename:FILE_NAME];
NSDictionary* attrs = [fm attributesOfItemAtPath:path error:nil];

if (attrs != nil) {
    return (NSDate*)[attrs objectForKey: NSFileCreationDate];
} else {
    return nil;
}

This always returns nil. Typing 'po attrs' into the debugger to get the list of key/value pairs in the NSDictionary returns the following..

NSFileGroupOwnerAccountID = 20;
NSFileGroupOwnerAccountName = staff;
NSFileModificationDate = 2010-01-21 11:47:55 +0000;
NSFileOwnerAccountID = 501;
NSFileOwnerAccountName = ben;
NSFilePosixPermissions = 420;
NSFileReferenceCount = 1;
NSFileSize = 338;
NSFileSystemFileNumber = 2234;
NSFileSystemNumber = 42553324;
NSFileType = NSFileTypeRegular;

No creation date.. bah..

Anyone know another way of getting the creation date or does it just not exist in iOS?

回答1:

This code actually returns the good creation date to me:

NSFileManager* fm = [NSFileManager defaultManager];
NSDictionary* attrs = [fm attributesOfItemAtPath:path error:nil];

if (attrs != nil) {
    NSDate *date = (NSDate*)[attrs objectForKey: NSFileCreationDate];
    NSLog(@"Date Created: %@", [date description]);
} 
else {
    NSLog(@"Not found");
}

Are you creating the file inside the App? Maybe that's where the problem is.

回答2:

There is a special message fileCreationDate for that in NSDictionary. The following works for me:

Objective-C:

NSDate *date = [attrs fileCreationDate];

Swift:

let attrs = try NSFileManager.defaultManager().attributesOfItemAtPath(path) as NSDictionary
attrs.fileCreationDate()

回答3:

Swift 2.0 version:

do {
    let fileAttributes = try NSFileManager.defaultManager().attributesOfItemAtPath(YOURPATH)
    let creationDate = fileAttributes[NSFileCreationDate] as? NSDate
    let modificationDate = fileAttributes[NSFileModificationDate] as? NSDate
    print("creation date of file is", creationDate)
    print("modification date of file is", modificationDate)
}catch let error as NSError {
    print("file not found:", error)
}

回答4:

In Swift 4, if you want to know the file created date for a specific file in DocumentsDirectory, you can use this method

func getfileCreatedDate(theFile: String) -> Date {

        var theCreationDate = Date()
        do{
            let aFileAttributes = try FileManager.default.attributesOfItem(atPath: theFile) as [FileAttributeKey:Any]
            theCreationDate = aFileAttributes[FileAttributeKey.creationDate] as! Date

        } catch let theError as Error{
            print("file not found \(theError)")
        }
        return theCreationDate
    }

回答5:

  NSDate *creationDate = nil;
  if ([fileManager fileExistsAtPath:filePath]) {
       NSDictionary *attributes = [fileManager attributesOfItemAtPath:filePath error:nil];
       creationDate = attributes[NSFileCreationDate];
  }

Its here

回答6:

Updated answer for Swift 4 to pull out the modified (.modifiedDate) or creation (.creationDate) date:

let file: URL = ...
if let attributes = try? FileManager.default.attributesOfItem(atPath: file.path) as [FileAttributeKey: Any],
    let creationDate = attributes[FileAttributeKey.creationDate] as? Date {
    print(creationDate)
    }

Using a file that you provide in advance via a URL, it will request its attributes. If successful a dictionary of [FileAttributeKey: Any] is returned
Using the dictionary from step 1, it then pulls out the creation date (or modified if you prefer) and using the conditional unwrap, assigns it to a date if successful
Assuming the first two steps are successful, you now have a date that you can work with

回答7:

Swift 3 version code:

do {
        let fileAttributes = try FileManager.default.attributesOfItem(atPath: yourPathString)
        let modificationDate = fileAttributes[FileAttributeKey.modificationDate] as! Date
        print("Modification date: ", modificationDate)
    } catch let error {
        print("Error getting file modification attribute date: \(error.localizedDescription)")
    }

回答8:

Can you use fstat64 to get the st_birthtimespec member of the returned struct? You'll need to create a C file handle for the file and convert the timespec value into an NSDate, but that's better than nothing.

回答9:

In Swift 5:

let date = (try? FileManager.default.attributesOfItem(atPath: path))?[.creationDate] as? Date

来源：https://stackoverflow.com/questions/2108953/ios-how-do-you-find-the-creation-date-of-a-file

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