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- IBAN Validation check 5 answers
Help me please to design Regex that will match all IBANs with all possible whitespaces. Because I've found that one, but it does not work with whitespaces.
[a-zA-Z]{2}[0-9]{2}[a-zA-Z0-9]{4}[0-9]{7}([a-zA-Z0-9]?){0,16}
I need at least that formats:
DE89 3704 0044 0532 0130 00
AT61 1904 3002 3457 3201
FR14 2004 1010 0505 0001 3
Just for the example IBAN's from those countries :
Start with 2 letters then 2 digits.
Then allow a space before every 4 digits, optionally ending with 1 or 2 digits:
\b[A-Z]{2}[0-9]{2}(?:[ ]?[0-9]{4}){4}(?!(?:[ ]?[0-9]){3})(?:[ ]?[0-9]{1,2})?\b
Note that if the intention is to validate a complete string, that the regex can be simplified.
Since the negative look-ahead (?!...) won't be needed then.
And the word boundaries \b can be replaced by the start ^ and end $ of the line.
^[A-Z]{2}[0-9]{2}(?:[ ]?[0-9]{4}){4}(?:[ ]?[0-9]{1,2})?$
Also, that one can be simplified even more if having 4 groups of 4 connected digits doesn't matter.
^[A-Z]{2}(?:[ ]?[0-9]){18,20}$
Remarks
But if you want to match an IBAN number from accross the world?
Then the BBAN part of the IBAN is allowed to have up to 30 numbers or uppercase letters. Reference
And can be written with either spaces or dashes or nothing in between.
For example: CC12 XXXX 12XX 1234 1234 1234 1234 1234 123
So the regex to match a string with a long IBAN would become a bit longer.
^([A-Z]{2}[ \-]?[0-9]{2})(?=(?:[ \-]?[A-Z0-9]){9,30}$)((?:[ \-]?[A-Z0-9]{3,5}){2,7})([ \-]?[A-Z0-9]{1,3})?$
Also note, that a pure regex solution can't do calculations.
So to actually validate an IBAN number then extra code is required.
Example Javascript Snippet:
function smellsLikeIban(str){
return /^([A-Z]{2}[ \-]?[0-9]{2})(?=(?:[ \-]?[A-Z0-9]){9,30}$)((?:[ \-]?[A-Z0-9]{3,5}){2,7})([ \-]?[A-Z0-9]{1,3})?$/.test(str);
}
function validateIbanChecksum(iban) {
const ibanStripped = iban.replace(/[^A-Z0-9]+/gi,'') //keep numbers and letters only
.toUpperCase(); //calculation expects upper-case
const m = ibanStripped.match(/^([A-Z]{2})([0-9]{2})([A-Z0-9]{9,30})$/);
if(!m) return false;
const numbericed = (m[3] + m[1] + m[2]).replace(/[A-Z]/g,function(ch){
//replace upper-case characters by numbers 10 to 35
return (ch.charCodeAt(0)-55);
});
//The resulting number would be to long for javascript to handle without loosing precision.
//So the trick is to chop the string up in smaller parts.
const mod97 = numbericed.match(/\d{1,7}/g)
.reduce(function(total, curr){ return Number(total + curr)%97},'');
return (mod97 === 1);
};
var arr = [
'DE89 3704 0044 0532 0130 00', // ok
'AT61 1904 3002 3457 3201', // ok
'FR14 2004 1010 0505 0001 3', // wrong checksum
'GB82-WEST-1234-5698-7654-32', // ok
'NL20INGB0001234567', // ok
'XX00 1234 5678 9012 3456 7890 1234 5678 90', // smells ok
'YY00123456789012345678901234567890', // smells ok
'NL20-ING-B0-00-12-34-567', // wrong format, but valid checksum
'XX22YYY1234567890123', // wrong checksum
'foo@i.ban' // Not even smells like IBAN
];
arr.forEach(function (str) {
console.log('['+ str +'] Smells Like IBAN: '+ smellsLikeIban(str));
console.log('['+ str +'] Valid IBAN Checksum: '+ validateIbanChecksum(str))
});Here is a suggestion that may works for the patterns you provided:
[A-Z]{2}\d{2} ?\d{4} ?\d{4} ?\d{4} ?\d{4} ?[\d]{0,2}
Try it on regex101
Explanation
[A-Z]{2}\d{2} ?2 capital letters followed by 2 digits (optional space)\d{4} ?4 digits, repeated 4 times (optional space)[\d]{0,2}0 to 2 digits
You can use a regex like this:
^[A-Z]{2}\d{2} (?:\d{4} ){3}\d{4}(?: \d\d?)?$
This will match only those string formats
It's probably best to look up the specifications for a correct IBAN number. But if you want to have a regex similar to your existing one, but with spaces, you can use the following one:
^[a-zA-Z]{2}[0-9]{2}\s?[a-zA-Z0-9]{4}\s?[0-9]{4}\s?[0-9]{3}([a-zA-Z0-9]\s?[a-zA-Z0-9]{0,4}\s?[a-zA-Z0-9]{0,4}\s?[a-zA-Z0-9]{0,4}\s?[a-zA-Z0-9]{0,3})?$
Here is a live example: https://regex101.com/r/ZyIPLD/1
来源：https://stackoverflow.com/questions/44656264/iban-regex-design