Extract a specific string pattern from a String (swift 2)

Question

I have a app which detects the text in any image user takes from the app or from existing image using OCR. This is working but if image has lots of unnesseasry numbers with the number set i want, everything will be detected. So i want to extract the numbers which always has a pattern from the detected text string,

As an example, my string can be something like this,

"3456 7834 5623 iuhef654sca 869878zsc ttv"

I want to get only the "3456 7834 5623" part from the above string. Which has two spaces, three sets of 4 digits. How did i do it? what is the best way to accomplish it?

NSRegularExpression could be used, something like `^(\\d\\d\\d\\d ){3}`? — Larme, Sep 25 '17 at 11:17

score 0 · Accepted Answer · answered Sep 25 '17 at 11:33

0

You can use regex pattern "(\\d){4} (\\d){4} (\\d){4}" as follow:

let string = "3456 7834 5623 iuhef654sca 869878zsc ttv"
let pattern = "(\\d){4} (\\d){4} (\\d){4}"
if let range = string.range(of: pattern, options: .regularExpression) {
    print(string[range])  // "3456 7834 5623\n"
}

answered Sep 25 '17 at 11:33

Leo Dabus

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Thanks a lot for the help! Im using swift 2. Can you help me with swift 2 version of this? – Bishan Sep 25 '17 at 11:43
1

another regex patter you could use is "((\\d){4} ){2}(\\d){4}" – Leo Dabus Sep 25 '17 at 11:45
try rangeOfString instead and options set to NSStringCompareOptions.RegularExpressionSearch – Leo Dabus Sep 25 '17 at 11:49
something like `string.rangeOfString(pattern, options: NSStringCompareOptions.RegularExpressionSearch, range: nil, locale: nil)` – Leo Dabus Sep 25 '17 at 11:53

Extract a specific string pattern from a String (swift 2)

1 Answers1