C_DATE($testdate)
C_LONGINT($day;$month;$year)
C_TEXT$dateformat()

$testdate:=!01.02.03!

$day:=Day of($testdate)
$month:=Month of($testdate)
$year:=Num(Substring(String(Year of($testdate));Length(String(Year of($testdate)))))

Case of 
\ ($day=1) & ($month=2) & ($year=3)
$dateformat:="DMY"
\ ($day=1) & ($year=2) & ($month=3)
$dateformat:="DYM"
\ ($month=1) & ($day=2) & ($year=3)
$dateformat:="MDY"
\ ($month=1) & ($year=2) & ($day=3)
$dateformat:="MYD"
\ ($year=1) & ($day=2) & ($month=3)
$dateformat:="YDM"
\ ($year=1) & ($month=2) & ($day=3)
$dateformat:="YMD"
End case