NSScanner issue with finding numbers that begin with 0

Question

I having an issue using NSScanner.

I have this string: 195 058 042 yuiyui 123

and I'm trying to just return the integers. however, any number that contains a 0 before the space doesn't get scanned property.

 var note = "195 048 042 yuiyui 123"

let whitespaceAndPunctuationSet = NSMutableCharacterSet.whitespaceAndNewlineCharacterSet()
let numbersCharacterSet = NSCharacterSet.decimalDigitCharacterSet()

let stringScanner = NSScanner(string: note)

var value = 0
while stringScanner.scanInteger(&value) {
    print(value)
}

and this prints the following: 195 48 42

It it missing the 0 from '048' But I'm not sure why

it should print the following

195 048 42

Thanks

Integers don't have leading 0's, you can't scan it as an integer if you want to preserve that — dan, Apr 08 '16 at 19:21
Just try `let n = 000042 ; print(n)` , or enter "0 0 0 0 4 2" on your calculator :) — Martin R, Apr 08 '16 at 19:25
ah ok. that makes sense. So i guess i'll have to scan as a String right? — Tony, Apr 08 '16 at 19:39

score 1 · Accepted Answer · answered Apr 08 '16 at 22:42

If you want to capture numeric substrings insider the longer string, NSRegularExpression is more appropriate:

let note = "195 048 042 yuiyui 123"

let regex = try! NSRegularExpression(pattern: "\\d+", options: [])

regex.enumerateMatchesInString(note, options: [], range: NSMakeRange(0, note.characters.count)) { result, flag, stop in
    guard let match = result else {
        // result is nil
        return
    }

    let range = match.rangeAtIndex(0)
    print((note as NSString).substringWithRange(range))
}

NSScanner issue with finding numbers that begin with 0

1 Answers1