Check out example codes for "get icloud doc swift". It will help you in understanding the concepts better.

Code Example 1

class CloudDataManager {

static let sharedInstance = CloudDataManager() // Singleton

struct DocumentsDirectory {
    static let localDocumentsURL: NSURL? = NSFileManager.defaultManager().URLsForDirectory(NSSearchPathDirectory.DocumentDirectory, inDomains: .UserDomainMask).last! as NSURL
   static let iCloudDocumentsURL: NSURL? = NSFileManager.defaultManager().URLForUbiquityContainerIdentifier(nil)?.URLByAppendingPathComponent("Documents")

}


// Return the Document directory (Cloud OR Local)
// To do in a background thread

func getDocumentDiretoryURL() -> NSURL {
    print(DocumentsDirectory.iCloudDocumentsURL)
    print(DocumentsDirectory.localDocumentsURL)
    if userDefault.boolForKey("useCloud") && isCloudEnabled()  {
        return DocumentsDirectory.iCloudDocumentsURL!
    } else {
        return DocumentsDirectory.localDocumentsURL!
    }
}

// Return true if iCloud is enabled

func isCloudEnabled() -> Bool {
    if DocumentsDirectory.iCloudDocumentsURL != nil { return true }
    else { return false }
}

// Delete All files at URL

func deleteFilesInDirectory(url: NSURL?) {
    let fileManager = NSFileManager.defaultManager()
    let enumerator = fileManager.enumeratorAtPath(url!.path!)
    while let file = enumerator?.nextObject() as? String {

        do {
            try fileManager.removeItemAtURL(url!.URLByAppendingPathComponent(file))
            print("Files deleted")
        } catch let error as NSError {
            print("Failed deleting files : \(error)")
        }
    }
}

// Move local files to iCloud
// iCloud will be cleared before any operation
// No data merging

func moveFileToCloud() {
    if isCloudEnabled() {
        deleteFilesInDirectory(DocumentsDirectory.iCloudDocumentsURL!) // Clear destination
        let fileManager = NSFileManager.defaultManager()
        let enumerator = fileManager.enumeratorAtPath(DocumentsDirectory.localDocumentsURL!.path!)
        while let file = enumerator?.nextObject() as? String {

            do {
                try fileManager.setUbiquitous(true,
                    itemAtURL: DocumentsDirectory.localDocumentsURL!.URLByAppendingPathComponent(file),
                    destinationURL: DocumentsDirectory.iCloudDocumentsURL!.URLByAppendingPathComponent(file))
                print("Moved to iCloud")
            } catch let error as NSError {
                print("Failed to move file to Cloud : \(error)")
            }
        }
    }
}

// Move iCloud files to local directory
// Local dir will be cleared
// No data merging

func moveFileToLocal() {
    if isCloudEnabled() {
        deleteFilesInDirectory(DocumentsDirectory.localDocumentsURL!)
        let fileManager = NSFileManager.defaultManager()
        let enumerator = fileManager.enumeratorAtPath(DocumentsDirectory.iCloudDocumentsURL!.path!)
        while let file = enumerator?.nextObject() as? String {

            do {
                try fileManager.setUbiquitous(false,
                    itemAtURL: DocumentsDirectory.iCloudDocumentsURL!.URLByAppendingPathComponent(file),
                    destinationURL: DocumentsDirectory.localDocumentsURL!.URLByAppendingPathComponent(file))
                print("Moved to local dir")
            } catch let error as NSError {
                print("Failed to move file to local dir : \(error)")
            }
        }
    }
}



}

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