即使应用将被删除，如何在NSUserDefaults中保存数据？

Question

I save some strings and numbers to NSUSerDefault, but when I uninstall and reinstall the app the data is ereased.

Is there a possibility to store data some where else? Maybe in keychain?

Answer 1

There are two places where you can store data that will persist after an app is deleted, but in both cases, it's not hidden data, so if that's what you're looking for, you're out of luck.

Your two possibilities are 1) Saving data to the photo library. (However, you can't read it back unless you get the user to select the photo for you.) 2) The address book. This is one place where you can create an entry and select it without user input.

Answer 2

You could stash a small amount of data in the comments field of a keychain record.

However, I doubt Apple would allow it because it would violate the principle of sandboxing the apps. It's hard to think of a legitimate reason to have an app leave data behind after it's gone.