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VBScript DateAdd Function

VBScript Reference Complete VBScript Reference

The DateAdd function returns a date to which a specified time interval has been added.

Syntax

DateAdd(interval,number,date)

Parameter Description
interval Required. The interval you want to add

Can take the following values:

  • yyyy - Year
  • q - Quarter
  • m - Month
  • y - Day of year
  • d - Day
  • w - Weekday
  • ww - Week of year
  • h - Hour
  • n - Minute
  • s - Second
number Required. The number of interval you want to add. Can either be positive, for dates in the future, or negative, for dates in the past
date Required. Variant or literal representing the date to which interval is added

Example 1

'Add one month to January 31, 2000
document.write(DateAdd("m",1,"31-Jan-00"))

Output:
2/29/2000

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Example 2

'Add one month to January 31, 2001
document.write(DateAdd("m",1,"31-Jan-01"))

Output:

2/28/2001

Example

'Subtract one month from January 31, 2001
document.write(DateAdd("m",-1,"31-Jan-01"))

Output:
12/31/2000

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VBScript Reference Complete VBScript Reference

From http://www.w3schools.com (Copyright Refsnes Data)