CompuServe Thread

#Serialise – Schemas ??

2 messages in this thread
#30434From: Tarn Faulkner [MSFT]Jul 10, 1994 7:02 PM
Peter, >> I have a class within an application which I need to update. The class does not have a user version number implemented as it was never envisaged that the class would change, so I need a method of detecting if the class serialized from the disk is the old schema number or the new one. KBase article Q108370 (Example A) shows some example code for handling this situation, but I cannot get it to work as I cannot seem to trap the CArchiveException::badSchema within the classes 'Serialize' routine. << Is the exception being thrown but you are somehow not catching it? If you could post the TRY / CATCH block of your code that might give me an idea why the exception wasn't being caught. Thanks, Tarn Faulkner Microsoft Developer Support
#30659From: Rob WarrenJul 12, 1994 8:52 AM
Instead of messing around the the schema's we just always write a WORD as the first thing in each objects Serialize. This way our objects are self-updating. Also this is great because if we get a corrupt file and the WORD isn't valid we use AfxThrowFileException to stop the process.