Function GetAgeDetailFull in Crystal Report

สร้าง custom function ชื่อ  GetAgeDetailFull

Function (dateTimeVar p_BirthDay , dateTimeVar p_ApplyDay)
numberVar IntervalMonth ;
numberVar IntervalDay  ;
numberVar ISTodayAfter  ;
dateTimeVar BirthDay := p_BirthDay;
dateTimeVar ApplyDay := p_ApplyDay;
stringvar ReturnAge ;

IntervalDay := DATEDIFF('d', BirthDay, ApplyDay); 
IntervalMonth := DATEDIFF("m", BirthDay, ApplyDay);

if(DATEDIFF('d', DATEADD('y', DATEDIFF('y', BirthDay, ApplyDay), BirthDay), ApplyDay) > 0) then
      ISTodayAfter := -1 
else
      ISTodayAfter := 0 ;

if( IntervalDay < 0 ) THEN 
  ReturnAge := '' 
else if((DATEDIFF('y', BirthDay, ApplyDay)+ISTodayAfter) > -1 ) THEN       
  ReturnAge := totext(DATEDIFF('yyyy', BirthDay, ApplyDay)+ISTodayAfter,"##0")+'Y '+
               totext(datepart('m',datetime(tonumber(DATEDIFF('d',BirthDay , ApplyDay ))))-1,"#0")+'M '+
               totext(datepart('d',datetime(tonumber(DATEDIFF('d',BirthDay , ApplyDay ))))-1,"#0")+'D ';
  ReturnAge;


วิธีเรียก function GetAgeDetailFull({FieldName},CurrentDate);