FileMaker Pro Custom Functions

/* ------------------------------ Format_Expr version 1.0 ------------------------------ Formats a credit card expiration date, returning it in the form: "MM/YY". Dates < 1970 or > 2069 will return an error. You can edit the marked line at the bottom of the function to change output format. You can edit the marked error_message variable to change the value returned if there's an error. Accepts dates in the form: M/Y M/YY M/YYYY MM/Y MM/YY MM/YYYY MY MMY MMYY MYYYY MMYYYY "." (period) and "-" may be substituted for "/" This function does not accept dates in the format "MYY" since there are cases where you cannot distinguish MYY and MMY (112, 102, etc.) All characters but 1234567890, "/", "-" and "." are ignored. trendymoniker@gmail.com for bug reports, requests, or questions. Feel free to distribute and adapt as you wish. */ Let ( [ // EDIT THIS LINE TO CHANGE THE ERROR MESSAGE error_message = "Error" ; date_trimmed = GetAsText ( Filter ( Substitute ( ExpirationDate ; ["."; "/"]; ["-"; "/"] ); "1234567890/" ) ); cc_year_raw = Case ( PatternCount ( date_trimmed ; "/") = 1 ; Right ( date_trimmed ; Length ( date_trimmed ) - Position ( date_trimmed ; "/" ; 0 ; 1 ) ) ; PatternCount ( date_trimmed; "/") = 0 ; Case ( Length ( date_trimmed ) = 2 ; Right ( date_trimmed ; 1 ) ; Length ( date_trimmed ) = 3 ; Right ( date_trimmed ; 1 ) ; Length ( date_trimmed ) = 4 ; Right ( date_trimmed ; 2 ) ; Length ( date_trimmed ) = 5 ; Right ( date_trimmed ; 4 ) ; Length ( date_trimmed ) = 6 ; Right ( date_trimmed ; 4 ); ) ) ; cc_year = Case ( Length ( cc_year_raw ) = 4 ; cc_year_raw ; Length ( cc_year_raw ) = 2 ; Case ( Left ( cc_year_raw ; 1 ) = "7" ; "19" & cc_year_raw ; Left ( cc_year_raw ; 1 ) = "8" ; "19" & cc_year_raw ; Left ( cc_year_raw ; 1 ) = "9" ; "19" & cc_year_raw ; // Else "20" & cc_year_raw ) ; Length ( cc_year_raw ) = 1 ; "200" & cc_year_raw ) ; cc_month_raw = Case ( PatternCount ( date_trimmed ; "/" ) > 1 ; "Invalid Expiration Date" ; PatternCount ( date_trimmed ; "/" ) = 1 ; GetAsNumber ( Left ( date_trimmed ; Position ( date_trimmed ; "/" ; 0 ; 1 ) - 1 ) ) ; PatternCount ( date_trimmed ; "/" ) = 0 ; Case ( Length ( date_trimmed ) = 2 ; Left ( date_trimmed ; 1 ) ; Length ( date_trimmed ) = 3 ; Left ( date_trimmed ; 2 ) ; Length ( date_trimmed ) = 4 ; Left ( date_trimmed ; 2 ) ; Length ( date_trimmed ) = 5 ; Left ( date_trimmed ; 1 ) ; Length ( date_trimmed ) = 6 ; Left ( date_trimmed ; 2 ); ) ) ; // close case cc_month = Case ( Length ( cc_month_raw ) = 1 ; "0" & cc_month_raw ; Length ( cc_month_raw ) = 2 ; cc_month_raw ; ) ; error_flag = Case ( PatternCount ( date_trimmed ; "/") > 1 ; 1; PatternCount ( date_trimmed; "/") = 0 and Length ( date_trimmed ) < 2 ; 1; PatternCount ( date_trimmed; "/") = 0 and Length ( date_trimmed ) > 6 ; 1; Length ( date_trimmed ) > 7 ; 1; Length ( cc_year_raw ) ≠ 4 and Length ( cc_year_raw ) ≠ 2 and Length ( cc_year_raw ) ≠ 1 ; 1; Length ( cc_month_raw ) ≠ 2 and Length ( cc_month_raw ) ≠ 1 ; 1; GetAsNumber ( cc_year ) < 1970 ; 1; GetAsNumber ( cc_year ) > 2069 ; 1; GetAsNumber ( cc_month ) < 1 ; 1; GetAsNumber ( cc_month ) > 12 ; 1; // Else 0 ) ] ; Case ( IsEmpty ( date_trimmed ) ; "" ; error_flag ; error_message ; // EDIT THIS LINE TO CHANGE THE OUTPUT FORMAT cc_month & "/" & Right ( cc_year ; 2 ) // cc_month & "/" & cc_year // cc_month & Right ( cc_year ; 2 ) // cc_month & cc_year ) ) // end let
 Then copy & paste into FileMaker Advanced's Edit Custom Function window.