FileMaker Pro Custom Functions

/* Between ( text ; searchString1 ; occurrence1 ; include1_1 ; searchString2 ; occurrence2 ; include2_1) by Fabrice Nordmann, BH&A v.2, Mar 2007 v.1, Jan 2007 v.2 adds inclusion boolean parameters extracts the middle of a text in between delimiters, based on a search strings and an occurrence numbers occurrences can be positive (starting from the beginning of the text) or negative (starting from the end) see also Before After, and BetweenNext functions */ Let ([ _occurrence1 = Case ( occurrence1 = 0 ; 1 ; occurrence1 ) ; _occurrence2 = Case ( occurrence2 = 0 ; 1 ; occurrence2 ) ; _p1= Position ( text ; searchString1 ; Case ( _occurrence1 < 0 ; Length ( text ) ; 1 ) ; _occurrence1 ) + not GetAsBoolean ( include1_1 ) * Length ( searchString1 ) ; _p2= Position ( text ; searchString2 ; Case ( _occurrence2 < 0 ; Length ( text ) ; 1 ) ; _occurrence2 ) + GetAsBoolean ( include2_1 ) * Length ( searchString2 ) ] ; Middle ( text ; _p1 ; _p2 - _p1 ) )
 Then copy & paste into FileMaker Advanced's Edit Custom Function window.