How to detect total available/free disk space on the iPhone/iPad device?

Question

I\'m looking for a better way to detect available/free disk space on the iPhone/iPad device programmatically.
Currently I\'m using the NSFileManager to detect the disk s

Answer 1

Swift 5 extension for FileManager with proper error handling and no automatic string conversions (convert byte count to string as you prefer). Also follows FileManager's naming.

extension FileManager {
    func systemFreeSizeBytes() -> Result<Int64, Error> {
        do {
            let attrs = try attributesOfFileSystem(forPath: NSHomeDirectory())
            guard let freeSize = attrs[.systemFreeSize] as? Int64 else {
                return .failure(NSError(domain: "", code: 0, userInfo: [NSLocalizedDescriptionKey : "Can't retrieve system free size"]))
            }
            return .success(freeSize)
        } catch {
            return .failure(error)
        }
    }

    func systemSizeBytes() -> Result<Int64, Error> {
         do {
             let attrs = try attributesOfFileSystem(forPath: NSHomeDirectory())
             guard let size = attrs[.systemSize] as? Int64 else {
                 return .failure(NSError(domain: "", code: 0, userInfo: [NSLocalizedDescriptionKey : "Can't retrieve system size"]))
             }
             return .success(size)
         } catch {
             return .failure(error)
         }
     }
}

Example usage:

let freeSizeResult = FileManager.default.systemFreeSizeBytes()
switch freeSizeResult {
case .failure(let error):
    print(error)
case .success(let freeSize):
    let freeSizeString = ByteCountFormatter.string(fromByteCount: freeSize, countStyle: .file)
    print("free size: \(freeSizeString)")
}

Answer 2

Don't use 'unsigned', it is only 32 bits which will overflow past 4GB, which is less than the typical iPad/iPhone free space. Use unsigned long long (or uint64_t), and retrieve the value out of the NSNumber as a 64-bit int too using unsignedLongLongValue.

Answer 3

for Swift as UIDevice extension

extension UIDevice {
    func freeDiskspace() -> NSString {
        let failedResult: String = "Error Obtaining System Memory"
        guard let path = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true).last else {
            return failedResult
        }
        do {
            let dictionary = try NSFileManager.defaultManager().attributesOfFileSystemForPath(path)
            if let fileSystemSizeInBytes = dictionary[NSFileSystemSize] as? UInt,
                let freeFileSystemSizeInBytes =     dictionary[NSFileSystemFreeSize] as? UInt {
                    return "Memory \(freeFileSystemSizeInBytes/1024/1024) of \(fileSystemSizeInBytes/1024/1024) Mb available."
            } else {
                    return failedResult
            }
        } catch {
            return failedResult
        }
    }
}

How to use:

print("\(UIDevice.currentDevice().freeDiskspace())")

Output will be:

Memory 9656 of 207694 Mb available.

Answer 4

ChrisJF answer in Swift 2.1 version:

func freeSpaceInBytes() -> NSString{

    var remainingSpace = NSLocalizedString("Unknown", comment: "The remaining free disk space on this device is unknown.")

    do {

        let dictionary =  try NSFileManager.defaultManager().attributesOfFileSystemForPath(NSHomeDirectory())
        freeSpaceSize = (dictionary[NSFileSystemFreeSize]?.longLongValue)!
        remainingSpace = NSByteCountFormatter.stringFromByteCount(freeSpaceSize, countStyle: NSByteCountFormatterCountStyle.File)

    }
    catch let error as NSError {

        error.description
        NSLog(error.description)

    }

    return remainingSpace

}

Answer 5

If your looking to get the the remaining free space using Swift it is slightly different. You need to use attributesOfFileSystemForPath() instead of attributesOfItemAtPath():

func deviceRemainingFreeSpaceInBytes() -> Int64? {
    let documentDirectoryPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
    var attributes: [String: AnyObject]
    do {
        attributes = try NSFileManager.defaultManager().attributesOfFileSystemForPath(documentDirectoryPath.last! as String)
        let freeSize = attributes[NSFileSystemFreeSize] as? NSNumber
        if (freeSize != nil) {
            return freeSize?.longLongValue
        } else {
            return nil
        }
    } catch {
        return nil
    }
}

Edit: Updated for Swift 1.0
Edit 2: Updated for safety, using Martin R's answer.
Edit 3: Updated for Swift 2.0 (by dgellow)

Answer 6

For iOS >= 6.0 you can use the new NSByteCountFormatter. This code gets the number of free bytes remaining as a formatted string.

NSError *error = nil;
NSArray * const paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSDictionary * const pathAttributes = [[NSFileManager defaultManager] attributesOfFileSystemForPath:[paths firstObject] error:&error];
NSAssert(pathAttributes, @"");
NSNumber * const fileSystemSizeInBytes = [pathAttributes objectForKey: NSFileSystemFreeSize];
const long long numberOfBytesRemaining = [fileSystemSizeInBytes longLongValue];
NSByteCountFormatter *byteCountFormatter = [[NSByteCountFormatter alloc] init];
NSString *formattedNmberOfBytesRemaining = [byteCountFormatter stringFromByteCount:numberOfBytesRemaining];