Validation for 4 digit pin

Question

Hi, 
 
 I have requirement to validate 4-digit pin. Below are the requirement of the 4-digit number 
 1. pin should not allow sequential numbers 
 2. pin should not allow same numbers 
 
 example: 1234 or 4321 or 0000, 1111 or 4444 or 2222 or 3333 numbers are not allowed as a card pin. 
 
 can anyone please help me how to write logic for the validation. 
 
 thanks in advance!

Stefan Helzle · Accepted Answer

A first idea here. Not sure if it catches all edge cases.

a!localVariables(
  local!pins: {"7369", "1234", "4321", "0000", "1111", "4444", "2222", "3333"},
  a!forEach(
    items: local!pins,
    expression: and(
      fv!item <> concat(tointeger(left(fv!item, 1)) + enumerate(4)), /* positive sequence */
      fv!item <> concat(tointeger(left(fv!item, 1)) + enumerate(4) * -1), /* negative sequence */
      fv!item <> rept(mid(fv!item, 1, 1), 4), /* 4 times the first character */
      fv!item <> rept(mid(fv!item, 2, 1), 4), /* 4 times the second character */
      fv!item <> rept(mid(fv!item, 3, 1), 4), /* 4 times the third character */
      fv!item <> rept(mid(fv!item, 4, 1), 4) /* 4 times the fourth character */
    )
  )
)

Mounika Yalamanchili · Answer

a!localVariables( local!a: regexmatch( pattern:"^(?!.*?(?:012|123|234|345|456|567|678|789|987|876|765|654|543|432|321|210|(\d)\1\1))\d{4}$", searchString:9989, regexFlags:"gms" ) , local!a ) 
 Hi , can you check the above code by placing in expression rule working fine for me . if you don't find regexmatch() in your rule , then add "Regular expression functions" plugin

juergeng0002 · Answer

Hi, Here is a solution which covers all edge cases. (Some humble bragging) The expression rule 'isPinValid' provides an array as a result. The first item in the result is a Boolean indicating if the Pin is valid, the second item in the result is the validation message a!localVariables( /* Checks if the pin is compliant to the rules: has 4 digits, no sequences (ascending or descending) and not the same 4 digits */ /* Get the digits of the pin - ri!pin is in text format */ local!allDigits: tostring(ri!pin), local!count: len(local!allDigits), local!digits: a!forEach(items: enumerate(local!count),expression: tointeger(local!allDigits[fv!index])), /* Prep for the sequence test, calculating the difference between the digits - ldrop is for the edge case if the pin starts with a 1 */ local!seq:ldrop({0,local!digits} - {local!digits,0},1), /* Same digits? */ local!sd: if(1=length(union(local!digits,local!digits)),true,false), /* Check if we have a sequence of numbers e. g. 2345 or 8765 */ local!seq1: if(3<=length(wherecontains(-1,local!seq)),true,false), local!seq2: if(3<=length(wherecontains(1,local!seq)),true,false), /* Is the pin valid (true), or is one of the rules violated? (false) */ local!check: not(or(4<>local!count,local!sd,local!seq1,local!seq2)), { local!check, /* Providing the confirmation and/or error message */ a!match(value:true, whenTrue: count(local!digits)<>length(local!digits), then: "Pin can only contain Digits", whenTrue: local!check, then: "Pin is valid", whentrue:4<>local!count, then: "Pin has not 4 digits", whentrue: local!sd, then: "Pin can't have the same 4 digits", whenTrue: or(local!seq1,local!seq2), then: "Pin can't have digits in " & if(local!seq1,"a","de") & "cending sequence", default: "Not a valid pin" ) } )

Sri Ram Kaja · Answer

Hi Druva , 
 Please try the below code. Here rule input (ri!pin) is of type text 
 if(
 and(
 len(ri!pin)=4,
 len(tostring(tointeger(ri!pin)))=len(ri!pin)
 ),
 a!localVariables(
 local!numbersUsed:{
 int(charat(ri!pin,1)),
 int(charat(ri!pin,2)),
 int(charat(ri!pin,3)),
 int(charat(ri!pin,4))
 },
 if(
 length(union(local!numbersUsed,local!numbersUsed))<>length(local!numbersUsed),
 "numbers cannot be repeated in pin",
 if(
 and(
 local!numbersUsed[1]+1=local!numbersUsed[2],
 local!numbersUsed[2]+1=local!numbersUsed[3],
 local!numbersUsed[3]+1=local!numbersUsed[4],
 ),
 "cannot be sequentail numbers",
 "no error"
 )
 )
 ),
 "pin should be 4 characters and should contain only numbers"
)

Validation for 4 digit pin

Top Replies