Regex to find and replace digits - ios

Question

I am new to regular expressions and need to perform a specific task with the same. I would require a regex that performs global search and checks if there are 3 or more consecutive digits in a string and if yes, then replaces all the digits with "xxxx".
For example, the string
abcdef 12 quews 4567
should be changed to
abcdef XX quews XXXX
Any help would be appreciated. Thanks.

Answer 1

UPDATED
Use this
func testingRegex6(text:String) ->String{
do{
var finalText = text
let componentNSString = NSString.init(string:text)
let regex = try NSRegularExpression(pattern: "\\d+", options:[.dotMatchesLineSeparators])
let matches = regex.matches(in: text ,options: [], range: NSMakeRange(0, componentNSString.length)).reversed()
if(matches.filter({$0.range.length >= 3}).count > 0) { //here we check if we have any substring containing 3 o more digits
for result3 in matches {
finalText = finalText.replacingOccurrences(of: componentNSString.substring(with: result3.range), with: Array(repeating: "X", count: result3.range.length).joined())
}
}
return finalText
}
catch{
return ""
}
return ""
}
Input "abcdef 12 quews 4567" Log "abcdef XX quews XXXX"
Input "abcdef 12 que82ws 45" Log "abcdef 12 que82ws 45"

Answer 2

With Reg. expression
let txt = "abc 12 wqer 987asd asdf1233sadf"
do {
let regx = try NSRegularExpression(pattern: "[0-9]", options: .caseInsensitive)
let result = regx.stringByReplacingMatches(in: txt, options: .withTransparentBounds, range: NSMakeRange(0, txt.count), withTemplate: "X")
print(result)
} catch {
print(error)
}
Without reg. expression
let txt = "abc 12 wqer 987asd asdf1233sadf"
let replacedStr = String(txt.map {
let c = String($0)
if let digit = Int(c), digit >= 0, digit <= 9 {
return "X"
} else {
return $0
}
})
print(replacedStr)

Answer 3

let str = "this is 123 my vie22w"
Convert string into string array
let characters = Array(str)
Use loop with counter and replace string if digits are more than 3.
var count = 0
for i in characters {
if i >= "0" && i <= "9" {
count += 1
}
}
if count > 3 {
let output = str.replacingOccurrences(of: "[\\[\\]^[0-9]]", with: "X", options: .regularExpression, range: nil)
print(output)
}

Answer 4

Use this,
let testString = "abcdef 12 quews 4567"
let output = testString.replacingOccurrences(of: "[\\[\\]^[0-9]]", with: "X", options: .regularExpression, range: nil)
print(output)
Your output looks like this,
abcdef XX quews XXXX
Update
Find String extension class,
extension String {
func matches(for regex: String) -> [String] {
do {
let regex = try NSRegularExpression(pattern: regex)
let results = regex.matches(in: self, range: NSRange(self.startIndex..., in: self))
return results.map {
String(self[Range($0.range, in: self)!])
}
} catch let error {
print("invalid regex: \(error.localizedDescription)")
return []
}
}
}
and find below code,
let temp = "abc44def 12 quews 4564 1254"
let array = temp.matches(for: "\\d{3,}")
var output = temp
for val in array.enumerated() {
var string = ""
for _ in 0..<val.element.count {
string+="X"
}
output = output.replacingOccurrences(of: val.element, with: string)
}
print(output)
you will get output like this,
abc44def 12 quews XXXX XXXX

Answer 5

Thank you for all your answers, with all your inputs I was able to solve this with following code
extension String {
func replaceDigits() -> String {
do {
let regex = try NSRegularExpression(pattern: "\\d{3,}", options: [])
let matches = regex.numberOfMatches(in: self, options: [], range: NSRange(location: 0, length: self.count))
if matches > 0 {
return replacingOccurrences(of: "\\d", with: "X", options: .regularExpression, range: nil)
}
} catch {
return self
}
return self
}
}