Persist current data stored in isolated storage through a Windows Phone 7 Marketplace update?

1
votes

In my experience, releasing a Windows Phone 7 app/game update will erase the isolated storage of the app.

If my user has already saved a lot of preferences (and I'm using isolated storage on the device to save this data), can I persist the data I've stored across an application update released through the Marketplace?

It's a bad user experience right now for them to download an app update and have all their preferences wiped.

2
windows-phone-7.1isolatedstoragewindows-phone-7

2 Answers

4
votes

How are you storing the data you are expecting to persist?

The contents of IsolatedStorage should not normally be affected by installing an update but there are a few scenarios which may lead to your experience.

  • If you're storing data in IsolatedStorageSettings but change the assembly which access these in the update. (The assembly name is used as part of the key to access this data so it will be looking in a different place after the update.)
  • You are serializing/deserializing a model to the isostore and the updated version of the file in the new version can't deserialize the old version of the model. (You should specifically handle such situations.)
  • You specifically deploy an empty file to isostore on first run, but don't check if a reinstall.
2
votes

In my experience, releasing a windows phone 7 app/game update will erase the isolated storage of the app.

To bad, your "experience" is wrong. Updating a application will not erase the isolated storage for the app.