http://www.scriptlogic.com/kixtart UDF: DateMath()

FUNCTION DateMath ($expd1, $expd2)
  ; Author: ScriptLogic Corporation
  ; if both parameters are dates (yyyy/mm/dd), a positive integer indicating
  ; the days between the two dates will be returned.
  ; if the first is a date (yyyy/mm/dd) and the second is an integer
  ; (number of days), a new date will be returned.
  ;
  ; UDF dependencies: SerialDate, Abs

  SELECT
  CASE InStr($expd1,'/') AND InStr($expd2,'/')
    ; two date passed - return daysbetween integer
    $datemath=serialdate($expd1)-serialdate($expd2)
    IF ($datemath < 0)
      $datemath=$datemath*-1
    ENDIF
  CASE InStr($expd1,'/') AND 1-InStr($expd2,'/')
    ; date and a number passed - return date
    $expd2=0+$expd2
    $datemath=serialdate(serialdate($expd1)+$expd2)
  CASE 1
    ; incorrect parameters passed
  ENDSELECT
ENDFUNCTION ; - DateMath -

25 March 2002	DateMath()
Author	ScriptLogic Corporation
Action	Performs mathematical computations on a date or computers days between two dates.
Syntax	DateMath ("date1", "date2") -or- DateMath ("date1", integer)
Parameters	date1 (Required / String) A date in the form of "YYYY/MM/DD" date2 -or- integer (Required / String) A date in the form of "YYYY/MM/DD" or an integer (positive or negative)
Remarks	Date parameters must be in the form of YYYY/MM/DD.
Returns	If two dates are passed, the number of days between them is returned as in integer. If a date is passed as "date1" and a number of days is passed as integer, the resulting date will be returned in the form of YYYY/MM/DD.
Dependencies	SerialDate()
Examples	$DaysBetween=Datemath("2001/04/01","1999/01/01") $LastWeek=DateMath(@Date,-7)
Source	FUNCTION DateMath ($expd1, $expd2) ; Author: ScriptLogic Corporation ; if both parameters are dates (yyyy/mm/dd), a positive integer indicating ; the days between the two dates will be returned. ; if the first is a date (yyyy/mm/dd) and the second is an integer ; (number of days), a new date will be returned. ; ; UDF dependencies: SerialDate, Abs SELECT CASE InStr($expd1,'/') AND InStr($expd2,'/') ; two date passed - return daysbetween integer $datemath=serialdate($expd1)-serialdate($expd2) IF ($datemath < 0) $datemath=$datemath*-1 ENDIF CASE InStr($expd1,'/') AND 1-InStr($expd2,'/') ; date and a number passed - return date $expd2=0+$expd2 $datemath=serialdate(serialdate($expd1)+$expd2) CASE 1 ; incorrect parameters passed ENDSELECT ENDFUNCTION ; - DateMath -

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