It's
after-hours now so you might have sorted this already - but fwiw they are used
by cached updates and, mostly, TUpdateSQL so that you can construct queries
like: UPDATE TableX SET FieldY = NewValue WHERE TableID = Z AND FieldY =
OldValue (ie "upWhereChanged" setting). They are available to the
application under these circumstances also - ie cached updates and once the data
has changed.
Some
people have problems with cached updates (they don't resolve changed data
clashes as well as client data sets) but I haven't had an issue with them in the
stuff I've done over the last year or so.
Also -
in BeforePost the table value and the buffer are different (old and new value) -
you can also use OnValidate where the control value and the buffer value are
different.
Max
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Peter G Jones
Sent: Friday, 25 June 1999 12:08
To: Multiple recipients of list delphi
Subject: [DUG]: NewValue, OldValue, CurValue
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Peter G Jones
Sent: Friday, 25 June 1999 12:08
To: Multiple recipients of list delphi
Subject: [DUG]: NewValue, OldValue, CurValue
It's Friday so excuse me if I'm thick but TField has 4
properties: Value, NewValue, OldValue & CurValue. I need to do
some BeforePost validation and was hoping to be able to use these
properties to determine if the field has changed and if so, to what value.
Sometimes I'm more interested in what it was (oldvalue).
My problem is that these properties either have Null,
Unassigned or the new value - never the old value. How does this work
- or doesn't it?
--------------------------
Peter G Jones
-------------------------
Peter G Jones
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