Using Try-Catch is the recommended approach check if there is a previously saved state that can be loaded. The Persistence Framework does not provide any built-in tools to check if there are available states.
Nevertheless, if you are using the AppDataStorageProvider (the default one) you can check if there is a file with the same name as the value of StorageProviderKey property located in the App_Data folder, but again using Try-Catch is the correct way to handle this case.
All the best,
the Telerik team
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