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 FileMaker Pro Custom Functions

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MonthLen ( themonth ; theyear )

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Theo Ros, *

Returns the number of days in the given month of the given year

Sample Input:
MonthLen ( 2 ; 1900 )
Sample Output:

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

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Because the MonthLength() function by Andrew Sasaki uses the Julian Calendar method of determining the leapyear, the results can be wrong.

This better function works for both the Julian and the Gregorian calendar

Returns the length of the month given in the year given

Return type: Number
Syntax: MonthLen ( themonth ; theyear )

In: themonth - integer value ( 1-12 ). If empty, the current
month is assumed
theyear - the year to check (not a date, but an integer)
if theyear is earlier than 1583, the Julian Calendar
is assumed.
If empty, the current year is assumed

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


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