Date Parameter to UFL 1

[dugjohnson]

I am writing a UFL that figures lag time between a customer contact and response by tech support, pulling out non-working days.
One of my functions
Boolean: IsBusinessDay(Date)
takes a date as a parameter. As a test I am passing it CDate('01/01/2004') which is showing up in Delphi as 2453005 and translates to a date sometime in the year 8214.
How are dates passed to a UFL (it appears to be a long integer) and how does it translate to a date? My understanding was that it was the number of days after 12/31/1899, but that does not appear to be the case. Thanks in advance.
Doug
P.S. I have written UFLs with string parameters to good effect so I assume my basic technique is OK...time to branch out.

 

[synapsevampire]

An interesting approach, however creating a Periods table is the industry standard, a required dimension for Data Marts, which eliminates the requirement for writing and maintaining code for this sort of thing, and much more:

faq767-4532

-k

 

[dugjohnson]

And if I controlled the horizontal and vertical of this internal app, I would do that. This function is just one of several that I am working on.
I am still in the dark as to how a date is passed to a UFL.
Doug

 

[DjangMan]

I seem to recall that the date that is passed is a Julian date so you need to convert using a Julian Date offset. Here's a function that I wrote to tell me if a date is within a month:

const
  JulianDateOffset = 2415018;

<snip>

function InMonth (ParamBlock : PUFParamBlock) : UFError;
var 
     Param1 : PUFParamListElement; //a pointer to the first parameter
     Param2 : PUFParamListElement; //a pointer to the second parameter
     D1     : UFTDate;
     D2     : UFTDate;

     i      : boolean;

begin

     Param1 := GetParam (ParamBlock, 1); //the first param is the string to trim
     Param2 := GetParam (ParamBlock, 2); //the second param is the character to trim

     //check if the correct number of parameters is passed to our function

     if (Param1 = nil) or (Param2 = nil) then
     begin

         Result := UFNotEnoughParameters;
         EXIT;
         
     end;

     //is the param1 date in the same month as the param2 date?

     D1 := Param1^.Parameter.ParamDate - JulianDateOffset;
     D2 := Param2^.Parameter.ParamDate - JulianDateOffset;

     i := false;
     
     if Year(D1) = Year(D2) then 
         if Month(D1) = Month(D2) then
             i := true;

     ParamBlock^.ReturnValue.ReturnBoolean := smallint(i);

     result := UFNoError;
end;

Good luck!

Django

 

[dugjohnson]

Django, you rock. That is exactly the info that I needed. The other info on how to redesign futures apps was also valuable for my brain needs, but this solved the current emergency.