Re: Multiple Step Operation - THE TRICK!


This is even worse, stupidly worse that one could think...

Let's see the situation:
I got a DBGrid with lookupfields from where the enduser can
dynamically select a value (say, 'designation) from a table.
Inturn, selecting a value from the LookupResultField returns a
coded value in another field (say, 'Code').
While creating a new record, I had that Multiple-Step Operation
error while attempting to select a value from the drop-down
list (within the DBGrid). Of course, I suspected uninitialized
values to cause the error, so I fixed that in the OnNewRecord
event of the TADOTable, giving 'Code' a known - not null value.
Even though... I then suspected some type mismatch
(OLEVarriants etc...) so I carrefully typecasted assignated
params... still the same.

No, falks, if you face that same problem, don't look for a
solution within the code: just set the DisplayWidth property
of the LookupField to a larger value, so that the internally
called Lookup method of the Dataset takes the entire String
('designation') otherwise it gets truncated... and do not
return a valid result.

Unbelievable? So did I say, just try out and tell me I'm wrong..

Still, what DO actually generate this exception?... Seems generic?

.