Saving NSMutableArray with NSUserDefaults in Swift Returns Nil

问题

I have a NSMutableArray. Here is how I save it with NSUserDefaults:

var defaults = NSUserDefaults.standardUserDefaults()
defaults.setObject(downloadedFile as NSMutableArray, forKey: "myKey")

And here how I retrieve it:

var downloadedFilesFromUserDefaults:NSMutableArray = defaults.objectForKey("myKey") as NSMutableArray

回答1:

take look at this and try to save you array like this! as this worked perfectly!

var arr:NSMutableArray = NSMutableArray(objects: "ASD","aSd")
    NSUserDefaults.standardUserDefaults().setObject(arr, forKey: "Array")
    NSUserDefaults.standardUserDefaults().synchronize()

on button click

NSLog("%@", NSUserDefaults.standardUserDefaults().objectForKey("Array") as NSMutableArray)

回答2:

It looks like swift somehow release my object i needed to make sure that my object is not nil.

来源：https://stackoverflow.com/questions/26798236/saving-nsmutablearray-with-nsuserdefaults-in-swift-returns-nil