how to use writeToFile to save image in document directory?
问题 // directoryPath is a URL from another VC @IBAction func saveButtonTapped(sender: AnyObject) { let directoryPath = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)[0] as NSURL let urlString : NSURL = directoryPath.URLByAppendingPathComponent("Image1.png") print("Image path : \(urlString)") if !NSFileManager.defaultManager().fileExistsAtPath(directoryPath.absoluteString) { UIImageJPEGRepresentation(self.image, 1.0)!.writeToFile(urlString