Helen,

Thanks for that.

I can understand why the fields should be read-ony. In fact I do not
want the users to be able to edit them. I simply want to assign them
a value in the oncalc event which is displayed to the user.

I am a bit confused however by this paragraph:

> A calculated field ONLY exists as the result of a calculation - you

cannot assign a value to it. Calculated fields (whether originating
from the database via COMPUTED BY or calculated in client code) are
always read-only.

I have been using a TIBoTable. I don't appear to have a problem
with queries - they allow me process the oncalc field fine. It is
only when I use calc fields in the tibotable.

I did the following:

1. Placed a tibotable on the form and assigned it to a table
2. Double clicked the table to bring up the fields editor
3. In the FE, I added all fields, then a new field , type calculated
and called it tbLeadHdrLdh_name_details, type string, 30 chars
and in my oncalc event:

tbLeadHdrLdh_Name_Details.AsString:='Details: '+

tbLeadHdrLdh_FirstName.AsString+', '+tbLeadHdrLdh_SurName.AsString

This causes the exception 'dataase not in edit mode'

Any help would be appreciated,

Thanks & Regards,

Stewart Bourke.

--- In IBObjects@y..., Helen Borrie <helebor@w...> wrote:
> At 03:10 AM 04-03-01 +0000, you wrote:
> >This is probably not only an IBO situation but I have a question
> >regarding calculated fields on an IBOTable.
> >
> >I have defined a calculated field which is evaluated in the
> >oncalcfields event. My problem is that I am getting an
> >error 'dataase not in edit mode' every time I assign the
calculated
> >field a value in the oncalcfield event, when the table's state is
> >dsBrowse.
>
> A calculated field ONLY exists as the result of a calculation - you
cannot assign a value to it. Calculated fields (whether originating
from the database via COMPUTED BY or calculated in client code) are
always read-only.
>
> To solve the problem of the real data columns being not editable,
if you are using TIBOQuery, instantiate the field object of the calc.
field and set its FieldKind to fkCalculated. If you are using
TIB_Query, double-click on the query object to open the Fields Editor
and set the field's COMPUTED attribute true.
>
> hth
>
> Helen
>
>
> >I can understand the logic (I Think!) behind this from the
> >point of view that I am assigining a value to a field from the
> >dataseset, which it then attempts to write to the database, My
> >question is how do I stop it.
> >
> >Is there a way to have the oncalcfield event fire and to be able
to
> >assign the calculated field value without the table objecting.
> >Similar calculated fields work fine in an IBOQuery - but the
again
> >the result set will not be live.
> >
> >Thanks,
> >Stewart Bourke
> >
> >
> >
> >
> >
> >
> >
> >Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
>
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> InterBase Developer Initiative · http://www.interbase2000.org
> _______________________________________________________