What version of IBO are you using?
Part of the problem has to do with me using the extended type in delphi to
contain the value rather than a double. This is an area I've only partially
addressed with the 3.4 release. Perhaps what I did in this release will be
sufficient. Please get the latest and let me know. Use the eval version if
you need to.

Thanks,
Jason Wharton

----- Original Message -----
From: "Helmut Steinberger" <ibo@...>
To: <IBObjects@yahoogroups.com>
Sent: Monday, November 17, 2003 2:47 AM
Subject: [IBO] UDF Parameter Bug in IBO ????


> Hello,
>
> I think I discovered a bug, when using UDFs.
> I use several UDFs, which I build by myself. Until I changed to FB1.5
> all UDFs worked well as expected, but now I discovered a strange
> behavior.
> I think IBO interprets the datatype of the paramters passed to the UDF
> wrong.
> The first and second parameter is interpreted right, but every further
> parameter is interpreted as the same type like the 2nd parameter.
>
> I give you an example to understand what I meen:
>
> The Pascal Code of the UDF :
>
> function test_udf (var intparam : integer;
> var intparam2 : integer;
> var doubleparam : double) : double; stdcall;
>
> begin
> doubleparam := (doubleparam + intparam + intparam2) / 2;
> result := doubleparam;
> end;
>
> The UDF is declared to FB like that:
>
> DECLARE EXTERNAL FUNCTION TEST_UDF
> integer,
> integer,
> double precision
> RETURNS double precision BY VALUE
> ENTRY_POINT 'test_udf' MODULE_NAME 'testlib'^
>
>
> When I pass the following statement
>
> select test_udf (1, 2, 2.9) from rdb$database in IBConsole I get the
> correct result 2.95
>
> Doing the same in EMS Interbasemanager also brings the same result.
>
> When I now change the statement to
> select test_udf (:a, :b, :c) from rdb$database
>
> I will be asked to enter the 3 parameters.
>
> I enter 1 for :a, 2 for :b and 2.9 for :c then I get the result 2.5
>
> The same problem occures, when I use it within my application,
> designed with IBO.
>
> I use IBO 4.3 and FB 1.5 RC7
>
> cu
> Helmut