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 FileMaker Pro Custom Functions

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_AddMonths ( vDate ; vAddMonths )

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  Average rating: 4.6  (20 votes)
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Makah Encarnacao, Soliant Consulting

Add x number of months to a given date

Sample Input:
_AddMonths ( "9/15/2017" ; 9 )
Sample Output:

 Then copy & paste into FileMaker Advanced's Edit Custom Function window.


This function will add months to a given date, for example 5/15/2014 + 3 months = 8/15/2014. It adds to the month value, and does not modify the day value (although FileMaker may automatically modify the day value if the resulting date is not valid). If you would like to subtract months instead of add months, you can tweak the custom function or see my function _SubtractMonths or enter a negative value for the 2nd parameter.

Note: these functions are not guaranteed or supported by Please contact the individual developer with any questions or problems.

This is my Custom Function and I want to edit it


Can be more simple! FileMaker automatically converts a month number greater than 12 to years

vMonth = Month( vDate);
vDay = Day( vDate);
vYear = Year( vDate)

Date( vMonth + vAddMonths; vDay; vYear)

Tim Anderson, Larbert
September 02, 2015 2:29pm

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