Hi,



I am developing an application by using IBX to connect with Firebird
database embedded based on VCL .NET platform.



It has a few frames each with a TIBDatabase, TIBTransaction and one or
more TIBDataset(s). And each frame is associated with a button in the
Main Form so that user can switch from one frame to another. When the
frame become active, the database will be connected and the datasets
will be opened. When the frame become inactive, the database will be
disconnected and the datasets will be closed.



Now the problem comes. When I switch frames, SOMETIMES the dataset(s)
could not open or partially open. When I call the
TIBDataset.open/prepare/ParamByName, I got error message say "The object
reference not set to an instance of an object". This is not happening
every time but fairly often.



I tried Firebird Embedded 1.5 and 2.0, both the same. But on Interbase
7.5, my application seems work very well.



Does any one have suggestion or know how to fix it?



Thanks in advance.





Lai Fu Yan





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