How to validate a password which must contain either number or alphabets(or both) as well as special characters?

Question

hi am currently using the following to validate the password but i want to include special characters also. Currently it contains only numbers and alphabets. Please help.

 - (BOOL)validatePassword:(NSString *) password{
    NSString *ACCEPTABLE_CHARECTERS = @"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
    NSCharacterSet *cs = [[NSCharacterSet characterSetWithCharactersInString:ACCEPTABLE_CHARECTERS] invertedSet];
    NSString *filtered = [[password componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];
    return [password isEqualToString:filtered];
}

You can look at [this post](http://stackoverflow.com/questions/15132276/password-validation-in-uitextfield-in-ios) or [This one](http://stackoverflow.com/questions/26423427/regular-expression-for-password-validation-objective-c) — manman, Oct 27 '15 at 05:07
You can look at [this post](http://stackoverflow.com/questions/15132276/password-validation-in-uitextfield-in-ios) or [This one](http://stackoverflow.com/questions/26423427/regular-expression-for-password-validation-objective-c) — manman, Oct 27 '15 at 05:08
Did you try adding the special characters to `ACCEPTABLE_CHARECTERS`? BTW - you misspelled "CHARACTERS". — rmaddy, Oct 27 '15 at 05:11

score 14 · Accepted Answer · edited Oct 27 '15 at 06:03

You can try this

- (BOOL)validatePassword:(NSString *) password{
    if(password.length == 0){
    return NO;
    }
    NSString *regex = @"^(?=(.*\d){2})(?=.*[a-zA-Z])(?=.*[!@#$%])[0-9a-zA-Z!@#$%]{8,}";
    NSPredicate *passwordPredicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
    return [passwordPredicate evaluateWithObject:password];
}

EXPLANATION

(?=(.*\d){2}) - uses lookahead (?=) and says the password must contain at least 2 digits

(?=.*[a-zA-Z]) - uses lookahead and says the password must contain an alpha

(?=.*[!@#$%]) - uses lookahead and says the password must contain 1 or more special characters which are defined

[0-9a-zA-Z!@#$%] - dictates the allowed characters

{8,} - says the password must be at least 8 characters long

It might need a little tweaking e.g. specifying exactly which special characters you need but it should do the trick.

@Daniella D'Cruz : if my answer is what you were looking for, you can accept it. — Piyush Sharma, Oct 28 '15 at 12:10

score 0 · Answer 2 · answered Oct 28 '15 at 10:04

-(BOOL)validatePassword:(NSString *) password{
    NSString *COMMON_CHARECTERS = @"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
    NSString *SPECIAL_CHARECTERS = @"@#$%^&*";
    NSCharacterSet *cs_common = [NSCharacterSet characterSetWithCharactersInString:COMMON_CHARECTERS];
    NSCharacterSet *cs_special = [NSCharacterSet characterSetWithCharactersInString:SPECIAL_CHARECTERS];
    NSString *filtere_common = [[password componentsSeparatedByCharactersInSet:cs_common] componentsJoinedByString:@""];
    NSString *filtere_special = [[password componentsSeparatedByCharactersInSet:cs_special] componentsJoinedByString:@""];
    BOOL valid = (password.length == (filtere_common.length + filtere_special.length));
    return valid;
}

score -1 · Answer 3 · edited May 23 '17 at 12:01

-1

You can use regex to identify use of special character. like

^([a-zA-Z+]+[0-9+]+[&@!#+]+)$

You can use character sets as well to validate password:- Check this link

edited May 23 '17 at 12:01

Community

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answered Oct 27 '15 at 05:12

KavyaKavita

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You mean `^[a-zA-Z0-9&@!#]+$` – rmaddy Oct 27 '15 at 05:48
@rmaddy yes ..... didn't get much time to look into it, but have already used this kind of solution. – KavyaKavita Oct 27 '15 at 06:15

How to validate a password which must contain either number or alphabets(or both) as well as special characters?

3 Answers3