How to set up uitextfield so what the user types has to meet specific criteria(ie. uppercase, number, etc.)?

Question

I'm trying to set up specific criteria the user must create in order to create a new account. The criteria is as follows:

Password must start with a letter
At least 1 upper case letter
At least 1 lower case letter
At least 1 number
At least 1 Special Character
The password may not contain username

There was more criteria but these are the ones giving me the most problems. Any help on any of them is greatly appreciated!

what is the problem with checking the password for all the constraints/criteria? — Dasem, Oct 17 '16 at 20:14
It helps if you show the code you have attempted. Other wise the question is to vague. Always try to include code and point to the area of issue. — MwcsMac, Oct 17 '16 at 20:24

alexburtnik · Accepted Answer · 2016-10-17T20:52:47.710

2

Try this method:

func validate(pass: String, userName: String) -> Bool {
    guard pass.characters.count > 0 else {return false }
    guard pass != userName else {return false }

    //Checks if the first character is a lowercase letter
    let firstIndex = pass.index(pass.startIndex, offsetBy: 1)
    guard pass.substring(to: firstIndex).rangeOfCharacter(from: CharacterSet.lowercaseLetters) != nil else { return false }

    guard pass.rangeOfCharacter(from: CharacterSet.uppercaseLetters) != nil else { return false }
    guard pass.rangeOfCharacter(from: CharacterSet.lowercaseLetters) != nil else { return false }
    guard pass.rangeOfCharacter(from: CharacterSet.decimalDigits) != nil else { return false }

    let characterSet = CharacterSet(charactersIn: "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLKMNOPQRSTUVWXYZ0123456789")
    guard pass.rangeOfCharacter(from: characterSet.inverted) != nil else { return false }

    return true
}

edited Oct 17 '16 at 20:52

answered Oct 17 '16 at 20:25

alexburtnik

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This is really good, is there a way to check if the first character of the uitextfield is a lowercase letter? – SwiftyJD Oct 17 '16 at 20:38
@SwiftyJD See the updated code. I've checked it, works fine. – alexburtnik Oct 17 '16 at 20:54
This works great! Thanks for your help – SwiftyJD Oct 17 '16 at 21:02
@SwiftyJD You're welcome. Happy coding ;) – alexburtnik Oct 17 '16 at 21:16

Adam Zarn · Answer 2 · 2016-10-17T20:28:07.950

-1

Create functions that loop through each character of the entered password and check to see if it is contained in a particular string. For the upper case letter, loop through each character of the password, like this:

for c in password.characters {
    if "ABCDEFGHIJKLMNOPQRSTUVWXYZ".range(of:String(c)) != nil {
        return
    }
}
//if for loop is exited, alert user that their password is invalid.

edited Oct 17 '16 at 20:28

answered Oct 17 '16 at 20:13

Adam Zarn

1,868
1
16
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I just tried this, I get an error " Cannot convert value of type 'String.CharacterView._Element' (aka 'Character') to expected argument type 'String'" – SwiftyJD Oct 17 '16 at 20:24
Sorry, try converting c to a string like this: String(c) – Adam Zarn Oct 17 '16 at 20:28

How to set up uitextfield so what the user types has to meet specific criteria(ie. uppercase, number, etc.)?

2 Answers2