重用安全范围书签

我用 NSUserDefaults 弄清楚了。

var userDefault = NSUserDefaults.standardUserDefaults()var folderPath: NSURL? {    didSet {        do { let bookmark = try folderPath?.bookmarkDataWithOptions(.SecurityScopeAllowOnlyReadAccess, includingResourcevaluesForKeys: nil, relativeToURL: nil) userDefault.setObject(bookmark, forKey: "bookmark")        } catch let error as NSError { print("Set Bookmark Fails: (error.description)")        }    }}func applicationDidFinishLaunching(aNotification: NSNotification) {    if let bookmarkData = userDefault.objectForKey("bookmark") as? NSData {        do { let url = try NSURL.init(byResolvingBookmarkdata: bookmarkData, options: .WithoutUI, relativeToURL: nil, bookmarkDataIsStale: nil) url.startAccessingSecurityScopedResource()        } catch let error as NSError { print("Bookmark Access Fails: (error.description)")        }    }}