Software Venture Consulting

FileMaker Pro downloads & Resources
FileMaker Custom Functions
FileMaker Web Viewer Examples
FileMaker Pro & Lasso Consulting
FileMaker Books
FileMaker Articles
FileMaker Error Reference

Free Web Tools
Free FileMaker Tools

Personal Pages

Shopping Cart
Shopping Cart


Free Newsletter


Privacy Policy

FileMaker is a registered trademark of FileMaker, Inc. in the U.S. and other countries.


 FileMaker Pro Custom Functions

List  |  Show Random  |  Upload  |  Add This to Your Site

FormatAsFileName ( text ; extension ; lengthLimit )

Rate this function:  

  Average rating: 4.3  (31 votes)
  Discuss this Custom Function

Jonathan Mickelson, Thought Development Corp.

Simplifies concatenation of a data into a suitable length OS filename.

Sample Input:
FormatAsFileName ( "Usr_" & Last_Name_Field ; "mpg" ; 15 )
Sample Output:

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



This function simplifies the formatting of the value of text into a standard format for use as a filename by an operating system. Its parameters also include the ability to define a filename extension and a character limit for the concatenation. All parameters but text may be null ("").

NOTE: The truncation character may be changed or made null ("") in the variable definitions within the function source.

text - any text expression or text field

extension - any text expression or text field representing an optional file extension. The extension parameter does not require a period (.) to be supplied and automatically adds one to the beginning of the extension, if an extension is supplied and the leftmost character is not already a period (.)

lengthLimit - any numeric expression, or field containing a number, which represents the maximum number of characters the resulting filename may contain, including any defined the extension parameter. For any positive numeric value, the function truncates any necessary characters from the right of the text parameter, adding a special truncation character (~ by default) before any defined extension. A zero or null ("") value will bypass this feature.

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


There are no comments yet. Be the first to post 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 7 + 7 =
Search for Custom Functions:

Custom Functions Widget
Download the Custom Function Dashboard Widget for OS X
Keep all the latest Custom Functions right at your fingertips!

Newest Custom Functions:

1. SortList ( theList )
  (Sat, Jun 23, 8:45am)
2. HexUUIDToNum_cf (_uuid)
  (Sat, Jun 16, 1:55pm)
3. httpResponseCode ( responseHeaders )
  (Tue, Jun 12, 10:40pm)
4. FindDuplicateCharacters ( string )
  (Fri, Jun 08, 5:01pm)
5. FieldRepetitionLast ( field ; maxRepetition )
  (Wed, Jun 06, 6:05pm)
6. CountModifiedRecords ( NameTimestampField ; StartTimestamp ; EndTimestamp )
  (Mon, May 28, 8:23am)
7. JSONArrayLength ( JSONArrayStr )
  (Fri, May 25, 7:46am)
8. interpolation (y1; y2; y3; x1; x2; x3; x1y1; x2y1; x1y2; x2y2; rnd)
  (Sat, May 19, 3:55am)

RSS Feed of Custom Functions