Brian Dunning's FileMaker Custom Functions

randomLetterString ( n ; string ; numOp )

Random string generator. You select length and whether or not to include numbers. Also, the random string may be added to a preset string to form the desired length.

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Bill Holt   Bill Holt - Show more from this author

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  Sample input:
randomLetterString ( 8 ; "" ; 0 )


randomLetterString ( 12 ; "FRONTEND" ; 1 )
  Sample output:



  Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

This string generator (a Custom Function in FM & or later) creates a result that is as random as the Filemaker Random function allows. It is recursive. That is, it selects the first character of the string, recalls itself to select and append the second character, and repeats the process until the desired length is achieved. If you enter a "1" as the third parameter, the digits - 0 to 9 - will be included in addition to the letters a to z.

rev: slight randomness flaw corrected, sprelling cheeker used.

You can make a 500 character random string as easily as a four character one. It's pretty quick - less than a second on a G4 Mac Mini for the 500 character string.

I've incorporated this into a process for generating passwords that are keyed to the name of the registrant, the name of the organization, and another check sum, which creates a ridiculously hard to break, checkable, random result.




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

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