Regular Expression for Password Validation Objective-C

Question

Can anyone Please Help me i need a regular expression Password Validation.

Condition : Password should be maximum of 8 characters numeric or alphabetic with atleast one special characters

Thanks in advance.

Simple use character range length and use NSScanner for string searching which types of characters is exist or not. — Tirth, Oct 17 '14 at 10:54
i mean a single special character only. `maximum of 8 characters` includes 0 also. — Avinash Raj, Oct 17 '14 at 10:55
the user should have the possibility to use more than 8 chars. — vikingosegundo, Oct 17 '14 at 11:27
I find regex (-only) approaches often limiting. you could break it down in several parts: 1: simple string operations to check it it has the right length, 2: regex to check if special chars are present, 3: regex or string operations to check that no whitespace is there. I wrote an article that also covers multi-step validating: http://blog.vikingosegundo.de/2014/07/16/lighter-viewcontrollers-block-based-intentions/ — vikingosegundo, Oct 17 '14 at 11:38

Xyzer · Accepted Answer · 2014-10-17T11:24:53.723

5

^(?=.{2,8}$)(?=.*?[A-Za-z0-9])(?=.*?[\W_])[\w\W]+

This regular expression allowes 2 to 8 character passwords. It requires to have at least 1 alphanumeric (letter/number) character and 1 non-alphanumeric character. You can test it here.

If you want to change the minimum characters required or higher the maximum. Just change the 2 or 8.

edited Oct 17 '14 at 11:24

answered Oct 17 '14 at 11:10

Xyzer

111
7

got warning : Unknown escape sequence '\W' – Dhaval Bhimani May 15 '19 at 10:00
@DhavalBhimani i got the same warning. Have you found any solution? – Shivani Bajaj Nov 29 '19 at 07:11

score 3 · Answer 2 · answered Oct 22 '16 at 05:57

SOLUTION :

-(BOOL)isValidPassword:(NSString *)checkString{
NSString *stricterFilterString = @"^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)(?=.*[$@$#!%*?&])[A-Za-z\\d$@$#!%*?&]{8,}";
NSPredicate *passwordTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", stricterFilterString];
return [passwordTest evaluateWithObject:checkString];
}

TEST :

 NSLog(@"%@", [self isValidPassword:@"D33p@k$235#@df"] ? @"YES" : @"NO");

OUTPUT :

YES

score 1 · Answer 3 · edited Jun 20 '20 at 09:12

Swift 3

check if the password lenght more than or equal 8 and have lowercase , uppercase ,decimalDigits and special characters like !@#$%^&*()_-+ is optional.

Why i not use regular expression ?

Because it's difficult to support reserved characters in regular expression syntax.

func isValidated(_ password: String) -> Bool {
    var lowerCaseLetter: Bool = false
    var upperCaseLetter: Bool = false
    var digit: Bool = false
    var specialCharacter: Bool = false

    if password.characters.count  >= 8 {
        for char in password.unicodeScalars {
            if !lowerCaseLetter {
                lowerCaseLetter = CharacterSet.lowercaseLetters.contains(char)
            }
            if !upperCaseLetter {
                upperCaseLetter = CharacterSet.uppercaseLetters.contains(char)
            }
            if !digit {
                digit = CharacterSet.decimalDigits.contains(char)
            }
            if !specialCharacter {
                specialCharacter = CharacterSet.punctuationCharacters.contains(char)
            }
        }
        if specialCharacter || (digit && lowerCaseLetter && upperCaseLetter) {
            //do what u want
            return true
        }
        else {
            return false
        }
    }
    return false
}
let isVaildPass:Bool = isValidated("Test**00+-")
print(isVaildPass)

Regular Expression for Password Validation Objective-C

3 Answers3

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