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 FileMaker Pro Custom Functions

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Operate ( Expression )

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  Average rating: 4.4  (31 votes)
  Discuss this Custom Function

Ibrahim Bittar Torres, Eikonsys

Evaluates expressions with sums, substractions, multiplications and divisions

Sample Input:
Operate ( "A15" + 5 )
Sample Output:

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

Click here to copy To Clip Manager if you have myFMbutler's Clip Manager installed


This simple function performs the 4 basic operations so you can use it as an autoenter calculation in a number field to enter not just numbers but operations between them. For example, if you want to input an initial balance in a number field you can input the actual number or the difference between Income and Outcome.

To avoid security issues with the evaluate function, it filters all values and keep only the numbers and the basic operators (+-*/).


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


This function may fail if you enter numbers with commas like $1,230+50.55. I changed the filter to remove commas and allow a few other math expressions.

Let (Final = Filter ( Expression ; "().+-*/^0123456789" ) ;
Evaluate ( Final ) )

This may then affect the ability to work in different countries.

Tim Cimbura, Minneapolis, MN
October 23, 2011 6:24am

Hi Tim, thank you very much.


Ibrahim Bittar, Leon, Mexico
October 23, 2011 9:06am

Make a comment about this Custom Function (please try to keep it brief & to the point). Anyone can post:

Your Name:
characters left. If you paste in more than 1500 characters, it will be truncated. Discuss the function - advertisements and other useless posts will be deleted.
Answer 6 + 6 =
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