FileMaker Pro Custom Functions

ParseTime ( timeText ) = /* This function parses and reformats time (hours and minutes) casually entered into a text field so that it can be converted to a valid time by Filemaker. It also includes tests so that, if an invalid time string is entered, it will return an error message instead of an invalid time. Further, it incorporates code from the TimeMask custom function written by Steve Gerow of Abrazos Data Consulting that logically assigns AM or PM to times entered without that data between 7am and 7pm. It handles military time correctly as well. Many thanks to Steve, and to Brian Dunning. */ Let ( [ nums = Filter ( timeText ; "0123456789" ) ; chars = Filter (Upper ( timeText ) ; "AMNP" ) ; lgthN = Length ( nums ) ; lgthC = Length (chars ) ; numTest = Case ( GetAsNumber ( nums ) < 1260 ; 1 ; GetAsNumber (nums ) < 2360 ; 2 ; 0 ) ; charTest = Case ( lgthC > 0 and lgthC < 3 ; 1 ; 0 ) ; mins = Case ( lgthN > 2 ; Right ( nums ; 2 ) ; "00" ) ; hrs = Case ( lgthN > 2 ; Middle ( nums ; 1 ; lgthN - 2 ) ; nums ) ; hrsN = GetAsNumber ( hrs ) ; minsTest = Case ( GetAsNumber ( mins ) > 59 ; 0 ; 1 ) ; hrs12 = Case ( numTest = 2 ; GetAsText ( hrsN - 12 ) ; hrsN = 0 ; "12" ; hrs ) ; suffix = Case ( charTest = 1 and ( PatternCount ( chars ; "A" ) or Exact ( chars ; "M" ) ) ; " AM" ; charTest = 1 and ( PatternCount ( chars ; "P" ) or Exact ( chars ; "N" ) ) ; " PM" ; charTest = 0 and Exact ( Left ( nums ; 1 ) ; "0" ) ; " AM" ; numTest = 2 and hrsN > 12 ; " PM" ; "" ) ; hrsTest = Case ( GetAsNumber ( hrs12 ) > 12 ; 0 ; 1 ) ; suffixTest = Case ( hrsN > 12 and Exact ( suffix ; " AM" ) ; 0 ; 1 ) ; inter = GetAsNumber ( hrs12 & mins ) ] ; Case ( numTest = 0 ; "INVALID TIME" ; minsTest = 0 ; "INVALID TIME" ; hrsTest = 0 ; "INVALID TIME" ; suffixTest = 0 ; "INVALID TIME" ; inter > 0 and inter < 700 ; Left ( inter ; 1 ) & ":" & Right ( inter ; 2 ) & If ( not IsEmpty ( suffix ) ; suffix ; " PM" ) ; inter >= 700 and inter < 1000 ; Left ( inter ; 1 ) & ":" & Right ( inter ; 2 ) & If ( not IsEmpty ( suffix ) ; suffix ; " AM" ) ; inter >= 1000 and inter < 1200 ; Left ( inter ; 2 ) & ":" & Right ( inter ; 2 ) & If ( not IsEmpty ( suffix ) ; suffix ; " AM" ) ; inter >= 1200 and inter < 1260 ; Left ( inter ; 2 ) & ":" & Right ( inter ; 2 ) & If ( not IsEmpty ( suffix ) ; suffix ; " PM" ) ; "INVALID TIME" ) )
 Then copy & paste into FileMaker Advanced's Edit Custom Function window.