Invalid Pointer operation
When trying to prevew a report (even from the designer), I get intermittently (95% of the time) an error 'Invalid Pointer Operation'. From my limited knowledge it seems to be happenng in the OnLoadFromStream event of the report pages. Only happening on one of my reports, but it is very similar in construction to most of my other ones. It uses dbexpress components with MySQL server and a dialog form providing params to a query that is linked in a master-detail way to another query.
I know this is a vauge description of the error, but it is a rather vague error - can't seem to work out why there is a problem with this one report. Any ideas of things to try would be welcome - the problem usually then results in access violations and a message about 'Unsupported FRF format' or something similar.
I know this is a vauge description of the error, but it is a rather vague error - can't seem to work out why there is a problem with this one report. Any ideas of things to try would be welcome - the problem usually then results in access violations and a message about 'Unsupported FRF format' or something similar.
Comments
2 ideas (sorry only ideas not solutions) :
1/ Your report is 'corrupted' may be the best way is to copy a good one and make it again !
2/ I fixed some pbs in my code with memecheck. Very easy to use (even if not well documented) :
http://v.mahon.free.fr/pro/freeware/memcheck
good luck...
I tried creating a new report from scratch, and still no luck
It seems to be related to a dialog form that I have feeding the query - I have two fastreport Date controls on the form (one for a start and one for an end date). Then I reference them in the query by comparing a database field to see if it is between two dates. Then I set these two date parameters to get their values from the Start and End date controls. I get the error whenever I have a date control linked to the query in this way (or just a plain edit control linked in the same way - being compared to a date database field). It often seems to just show the error when I exit the application. (no error appears if I don't set the two date parameters of the query to reference controls on the form). I am doing similar input of parameters to queries in other reports without problems (they just dont' reference date fields - usually numeric).
Is the suggestion about running the bug finding utility still worth trying even though I am essentially writing no code at all? - Or did you mena that I might find a bug in fastreport itself?
Thanks,
Tom Ward