如何检测 iPhone/iPad 设备上的总可用/空闲磁盘空间？

Question

我正在寻找一种更好的方法来以编程方式检测 iPhone/iPad 设备上的可用/空闲磁盘空间。
目前我正在使用 NSFileManager 来检测磁盘空间。以下是为我完成这项工作的代码的 sn-p：

-(unsigned)getFreeDiskspacePrivate {
NSDictionary *atDict = [[NSFileManager defaultManager] attributesOfFileSystemForPath:@"/" error:NULL];
unsigned freeSpace = [[atDict objectForKey:NSFileSystemFreeSize] unsignedIntValue];
NSLog(@"%s - Free Diskspace: %u bytes - %u MiB", __PRETTY_FUNCTION__, freeSpace, (freeSpace/1024)/1024);

return freeSpace;
}

我对上面的 sn-p 是否正确？或者有没有更好的方法来了解总可用/可用磁盘空间。
我必须检测总可用磁盘空间，因为我们必须阻止我们的应用程序在磁盘空间不足的情况下执行同步。

Answer 1

不要使用“无符号”，它只有 32 位，会溢出超过 4GB，这比典型的 iPad/iPhone 可用空间要少。使用 unsigned long long（或 uint64_t），并使用 unsignedLongLongValue 从 NSNumber 中检索值作为 64 位 int。

Answer 2

更新：由于这个答案已经过去了很长时间，并且添加了新的方法/API，请查看以下关于 Swift 等的更新答案；由于我自己没有使用过它们，所以我不能保证它们。

原答案： 我发现以下解决方案对我有用：

-(uint64_t)getFreeDiskspace {
    uint64_t totalSpace = 0;
    uint64_t totalFreeSpace = 0;
    NSError *error = nil;  
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);  
    NSDictionary *dictionary = [[NSFileManager defaultManager] attributesOfFileSystemForPath:[paths lastObject] error: &error];  

    if (dictionary) {  
        NSNumber *fileSystemSizeInBytes = [dictionary objectForKey: NSFileSystemSize];  
        NSNumber *freeFileSystemSizeInBytes = [dictionary objectForKey:NSFileSystemFreeSize];
        totalSpace = [fileSystemSizeInBytes unsignedLongLongValue];
        totalFreeSpace = [freeFileSystemSizeInBytes unsignedLongLongValue];
        NSLog(@"Memory Capacity of %llu MiB with %llu MiB Free memory available.", ((totalSpace/1024ll)/1024ll), ((totalFreeSpace/1024ll)/1024ll));
    } else {  
        NSLog(@"Error Obtaining System Memory Info: Domain = %@, Code = %ld", [error domain], (long)[error code]);
    }  

    return totalFreeSpace;
}

当设备连接到机器时，它会返回给我 iTunes 显示的大小。

Answer 3

使用 unsigned long long 修改源代码：

- (uint64_t)freeDiskspace
{
    uint64_t totalSpace = 0;
    uint64_t totalFreeSpace = 0;

    __autoreleasing NSError *error = nil;  
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);  
    NSDictionary *dictionary = [[NSFileManager defaultManager] attributesOfFileSystemForPath:[paths lastObject] error: &error];  

    if (dictionary) {  
        NSNumber *fileSystemSizeInBytes = [dictionary objectForKey: NSFileSystemSize];  
        NSNumber *freeFileSystemSizeInBytes = [dictionary objectForKey:NSFileSystemFreeSize];
        totalSpace = [fileSystemSizeInBytes unsignedLongLongValue];
        totalFreeSpace = [freeFileSystemSizeInBytes unsignedLongLongValue];
        NSLog(@"Memory Capacity of %llu MiB with %llu MiB Free memory available.", ((totalSpace/1024ll)/1024ll), ((totalFreeSpace/1024ll)/1024ll));
    } else {  
        NSLog(@"Error Obtaining System Memory Info: Domain = %@, Code = %d", [error domain], [error code]);  
    }  

    return totalFreeSpace;
}

编辑：似乎有人编辑此代码以使用“uint64_t”而不是“unsigned long long”。虽然在可预见的未来这应该没问题，但它们并不相同。 'uint64_t' 是 64 位，并且永远都是。 10 年后，'unsigned long long' 可能是 128。这是一个小问题，但为什么我使用 unsignedLongLong。

Answer 4

如果您需要带大小的格式化字符串，可以查看nice library on GitHub:

#define MB (1024*1024)
#define GB (MB*1024)

@implementation ALDisk

#pragma mark - Formatter

+ (NSString *)memoryFormatter:(long long)diskSpace {
    NSString *formatted;
    double bytes = 1.0 * diskSpace;
    double megabytes = bytes / MB;
    double gigabytes = bytes / GB;
    if (gigabytes >= 1.0)
        formatted = [NSString stringWithFormat:@"%.2f GB", gigabytes];
    else if (megabytes >= 1.0)
        formatted = [NSString stringWithFormat:@"%.2f MB", megabytes];
    else
        formatted = [NSString stringWithFormat:@"%.2f bytes", bytes];

    return formatted;
}

#pragma mark - Methods

+ (NSString *)totalDiskSpace {
    long long space = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil] objectForKey:NSFileSystemSize] longLongValue];
    return [self memoryFormatter:space];
}

+ (NSString *)freeDiskSpace {
    long long freeSpace = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil] objectForKey:NSFileSystemFreeSize] longLongValue];
    return [self memoryFormatter:freeSpace];
}

+ (NSString *)usedDiskSpace {
    return [self memoryFormatter:[self usedDiskSpaceInBytes]];
}

+ (CGFloat)totalDiskSpaceInBytes {
    long long space = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil] objectForKey:NSFileSystemSize] longLongValue];
    return space;
}

+ (CGFloat)freeDiskSpaceInBytes {
    long long freeSpace = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil] objectForKey:NSFileSystemFreeSize] longLongValue];
    return freeSpace;
}

+ (CGFloat)usedDiskSpaceInBytes {
    long long usedSpace = [self totalDiskSpaceInBytes] - [self freeDiskSpaceInBytes];
    return usedSpace;
}

Answer 5

对于 iOS >= 6.0，您可以使用新的 NSByteCountFormatter。此代码以格式化字符串的形式获取剩余的空闲字节数。

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];

Answer 6

如果您希望使用 Swift 获得剩余的可用空间，则略有不同。您需要使用 attributesOfFileSystemForPath() 而不是 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
    }
}

编辑：针对 Swift 1.0 更新
编辑 2：为安全起见已更新，using Martin R's answer.
编辑 3：为 Swift 2.0 更新（dgellow）

Answer 7

重要的澄清（至少对我来说）。如果我将 iPod 连接到我的 Mac，这是 iTunes 应用程序显示的信息。

当我使用上面的代码时：

long long freeSpace = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil]
                            objectForKey:NSFileSystemFreeSize] longLongValue];

NSString *free1 = [NSByteCountFormatter stringFromByteCount:freeSpace countStyle:NSByteCountFormatterCountStyleFile];

[label1 setText:free1];

NSString *free2 = [NSByteCountFormatter stringFromByteCount:freeSpace countStyle:NSByteCountFormatterCountStyleBinary];

[label2 setText:free2];

countStyle NSByteCountFormatterCountStyleFile 显示：17,41 GB

countStyle NSByteCountFormatterCountStyleBinary 显示：16,22 GB

16,22 GB (NSByteCountFormatterCountStyleBinary) 当我将 iPod 连接到我的 Mac 时，iTunes 应用程序会完全显示给我的数字。

Answer 8

我编写了一个类来使用 Swift 获取可用/已用内存。 演示地址：https://github.com/thanhcuong1990/swift-disk-status
Swift 4 已更新。

import UIKit

class DiskStatus {

    //MARK: Formatter MB only
    class func MBFormatter(_ bytes: Int64) -> String {
        let formatter = ByteCountFormatter()
        formatter.allowedUnits = ByteCountFormatter.Units.useMB
        formatter.countStyle = ByteCountFormatter.CountStyle.decimal
        formatter.includesUnit = false
        return formatter.string(fromByteCount: bytes) as String
    }


    //MARK: Get String Value
    class var totalDiskSpace:String {
        get {
            return ByteCountFormatter.string(fromByteCount: totalDiskSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.file)
        }
    }

    class var freeDiskSpace:String {
        get {
            return ByteCountFormatter.string(fromByteCount: freeDiskSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.file)
        }
    }

    class var usedDiskSpace:String {
        get {
            return ByteCountFormatter.string(fromByteCount: usedDiskSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.file)
        }
    }


    //MARK: Get raw value
    class var totalDiskSpaceInBytes:Int64 {
        get {
            do {
                let systemAttributes = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory() as String)
                let space = (systemAttributes[FileAttributeKey.systemSize] as? NSNumber)?.int64Value
                return space!
            } catch {
                return 0
            }
        }
    }

    class var freeDiskSpaceInBytes:Int64 {
        get {
            do {
                let systemAttributes = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory() as String)
                let freeSpace = (systemAttributes[FileAttributeKey.systemFreeSize] as? NSNumber)?.int64Value
                return freeSpace!
            } catch {
                return 0
            }
        }
    }

    class var usedDiskSpaceInBytes:Int64 {
        get {
            let usedSpace = totalDiskSpaceInBytes - freeDiskSpaceInBytes
            return usedSpace
        }
    }

}

演示

Answer 9

这是我的答案以及为什么它更好。

答案（斯威夫特）：

func remainingDiskSpaceOnThisDevice() -> String {
    var remainingSpace = NSLocalizedString("Unknown", comment: "The remaining free disk space on this device is unknown.")
    if let attributes = try? FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory()),
        let freeSpaceSize = attributes[FileAttributeKey.systemFreeSize] as? Int64 {
        remainingSpace = ByteCountFormatter.string(fromByteCount: freeSpaceSize, countStyle: .file)
    }
    return remainingSpace
}

答案（目标 C）：

- (NSString *)calculateRemainingDiskSpaceOnThisDevice
{
    NSString *remainingSpace = NSLocalizedString(@"Unknown", @"The remaining free disk space on this device is unknown.");
    NSDictionary *dictionary = [[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil];
    if (dictionary) {
        long long freeSpaceSize = [[dictionary objectForKey:NSFileSystemFreeSize] longLongValue];
        remainingSpace = [NSByteCountFormatter stringFromByteCount:freeSpaceSize countStyle:NSByteCountFormatterCountStyleFile];
    }
    return remainingSpace;
}

为什么更好：

• 利用 Cocoa 的内置库NSByteCountFormatter，这意味着无需从字节到千兆字节的疯狂手动计算。 Apple 会为您做到这一点！
• 易于翻译：NSByteCountFormatter 为您完成这项工作。例如。当设备的语言设置为英语时，字符串的大小为 248.8 MB，但设置为法语时，字符串的大小为 248,8 Mo，其他语言的字符串等等。
• 出现错误时会给出默认值。

Answer 10

ChrisJF 回答 Swift 2.1 版本：

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 11

对于 Swift 作为 UIDevice 扩展

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
        }
    }
}

使用方法：

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

输出将是：

Memory 9656 of 207694 Mb available.

Answer 12

我知道这篇文章有点老了，但我认为这个答案可以帮助别人。如果您想知道设备上已用/可用/总磁盘空间，您可以使用Luminous。它是用 Swift 编写的。你只需要打电话：

Luminous.System.Disk.freeSpace()
Luminous.System.Disk.usedSpace()

或

Luminous.System.Disk.freeSpaceInBytes()
Luminous.System.Disk.usedSpaceInBytes()

Answer 13

以下代码是 ChrisJF 之前提供的答案的 Swift 3.0 版本实现：

func freeSpaceInBytes() -> NSString {

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

    do {
        let dictionary =  try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())
        let freeSpaceSize = ((dictionary[FileAttributeKey.systemFreeSize] as AnyObject).longLongValue)!
        remainingSpace = ByteCountFormatter.string(fromByteCount: freeSpaceSize, countStyle: ByteCountFormatter.CountStyle.file)
    }
    catch let error {
        NSLog(error.localizedDescription)
    }

    return remainingSpace as NSString

}

Answer 14

上述代码的 Swift 实现：-

import UIKit

class DiskInformation: NSObject {

    var totalSpaceInBytes: CLongLong = 0; // total disk space
    var totalFreeSpaceInBytes: CLongLong = 0; //total free space in bytes

    func getTotalDiskSpace() -> String { //get total disk space
        do{
        let space: CLongLong = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())[FileAttributeKey.systemSize] as! CLongLong; //Check for home dirctory and get total system size
            totalSpaceInBytes = space; // set as total space
            return memoryFormatter(space: space); // send the total bytes to formatter method and return the output

        }catch let error{ // Catch error that may be thrown by FileManager
            print("Error is ", error);
        }
        return "Error while getting memory size";
    }

    func getTotalFreeSpace() -> String{ //Get total free space
        do{
            let space: CLongLong = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())[FileAttributeKey.systemFreeSize] as! CLongLong;
            totalFreeSpaceInBytes = space;
            return memoryFormatter(space: space);

        }catch let error{
            print("Error is ", error);
        }
        return "Error while getting memory size";
    }

    func getTotalUsedSpace() -> String{ //Get total disk usage from above variable
        return memoryFormatter(space: (totalSpaceInBytes - totalFreeSpaceInBytes));
    }

    func memoryFormatter(space : CLongLong) -> String{ //Format the usage to return value with 2 digits after decimal
        var formattedString: String;

        let totalBytes: Double = 1.0 * Double(space);
        let totalMb: Double = totalBytes / (1024 * 1024);
        let totalGb: Double = totalMb / 1024;
        if (totalGb > 1.0){
            formattedString = String(format: "%.2f", totalGb);
        }else if(totalMb >= 1.0){
            formattedString = String(format: "%.2f", totalMb);
        }else{
            formattedString = String(format: "%.2f", totalBytes);
        }
        return formattedString;
    }


}

从任何其他类调用它。

func getDiskInfo(){
        let diskInfo = DiskInformation();
        print("Total disk space is", diskInfo.getTotalDiskSpace(),"Gb");
        print("Total free space is", diskInfo.getTotalFreeSpace(),"Gb");
        print("Total used space is", diskInfo.getTotalUsedSpace(),"Gb");
    }

在测试返回值时，它与其他应用程序显示的相同。至少在我的 iPhone 6S+ 中。这只是上述答案的快速实施。对我来说，接受的答案不起作用。

Answer 15

使用新的准确 API 进行更新，以获取 iOS11 中可用磁盘的可用大小。 以下是新 API 资源密钥的说明：

#if os(OSX) || os(iOS)
/// Total available capacity in bytes for "Important" resources, including space expected to be cleared by purging non-essential and cached resources. "Important" means something that the user or application clearly expects to be present on the local system, but is ultimately replaceable. This would include items that the user has explicitly requested via the UI, and resources that an application requires in order to provide functionality.
/// Examples: A video that the user has explicitly requested to watch but has not yet finished watching or an audio file that the user has requested to download.
/// This value should not be used in determining if there is room for an irreplaceable resource. In the case of irreplaceable resources, always attempt to save the resource regardless of available capacity and handle failure as gracefully as possible.
@available(OSX 10.13, iOS 11.0, *) @available(tvOS, unavailable) @available(watchOS, unavailable)
public var volumeAvailableCapacityFor Usage: Int64? { return _get(.volumeAvailableCapacityForImportantUsageKey) }
#endif

我交叉比较了键“FileAttributeKey.systemFreeSize”和键“URLResourceKey.volumeAvailableCapacityForImportantUsageKey”的结果，发现结果从“volumeAvailableCapacityForImportantUsageKey返回>" 与 UI 上显示的可用存储完全匹配。 这是快速实现：

class var freeDiskSpaceInBytesImportant:Int64 {
    get {
        do {
            return try URL(fileURLWithPath: NSHomeDirectory() as String).resourceValues(forKeys: [URLResourceKey.volumeAvailableCapacityForImportantUsageKey]).volumeAvailableCapacityForImportantUsage!
        } catch {
            return 0
        }
    }
}

Answer 16

如果您想节省时间，请使用以下 CocoaPod 库。我没有使用它，但似乎它应该可以工作。

https://cocoapods.org/pods/SystemServices

Answer 17

您可以使用 Swift 4 和 extension 找到另一种解决方案，这是一个不错的选择。

这是UIDevice 扩展名。

extension UIDevice {

    func totalDiskSpaceInBytes() -> Int64 {
        do {
            guard let totalDiskSpaceInBytes = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())[FileAttributeKey.systemSize] as? Int64 else {
                return 0
            }
            return totalDiskSpaceInBytes
        } catch {
            return 0
        }
    }

    func freeDiskSpaceInBytes() -> Int64 {
        do {
            guard let totalDiskSpaceInBytes = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())[FileAttributeKey.systemFreeSize] as? Int64 else {
                return 0 
            }
            return totalDiskSpaceInBytes
        } catch {
            return 0
        }
    }

    func usedDiskSpaceInBytes() -> Int64 {
        return totalDiskSpaceInBytes() - freeDiskSpaceInBytes()
    }

    func totalDiskSpace() -> String {
        let diskSpaceInBytes = totalDiskSpaceInBytes()
        if diskSpaceInBytes > 0 {
            return ByteCountFormatter.string(fromByteCount: diskSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.binary)
        }
        return "The total disk space on this device is unknown"
    }

    func freeDiskSpace() -> String {
        let freeSpaceInBytes = freeDiskSpaceInBytes()
        if freeSpaceInBytes > 0 {
            return ByteCountFormatter.string(fromByteCount: freeSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.binary)
        }
        return "The free disk space on this device is unknown"
    }

    func usedDiskSpace() -> String {
        let usedSpaceInBytes = totalDiskSpaceInBytes() - freeDiskSpaceInBytes()
        if usedSpaceInBytes > 0 {
            return ByteCountFormatter.string(fromByteCount: usedSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.binary)
        }
        return "The used disk space on this device is unknown"
    }

}

及示例用法：

UIDevice.current.totalDiskSpaceInBytes()
UIDevice.current.totalDiskSpace()
UIDevice.current.freeDiskSpaceInBytes()
UIDevice.current.freeDiskSpace()
UIDevice.current.usedDiskSpaceInBytes()
UIDevice.current.usedDiskSpace()

Answer 18

这里是 FileManager 的 Swift 5 扩展，具有适当的错误处理和没有自动字符串转换（根据您的喜好将字节数转换为字符串）。也遵循FileManager的命名。

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)
         }
     }
}

示例用法：

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)")
}