Swift: Highlight matched text in String between square brackets

NSMutableAttributedString+Extend.swift

import UIKit

extension NSMutableAttributedString {
    
    func highlightTarget(target: String, color: UIColor) -> NSMutableAttributedString {
        let targetValue = String(target.characters.dropFirst().dropLast())
        let regPattern = "\\[\(targetValue)\\]"
        if let regex = try? NSRegularExpression(pattern: regPattern, options: []) {
            let matchesArray = regex.matchesInString(self.string, options: [], range: NSRange(location: 0, length: self.length))
            for match in matchesArray {
                let attributedText = NSMutableAttributedString(string: targetValue)
                attributedText.addAttribute(NSForegroundColorAttributeName, value: color, range: NSRange(location: 0, length: attributedText.length))
                self.replaceCharactersInRange(match.range, withAttributedString: attributedText)
            }
        }
        return self
    }
}

//Usage
let attributedString = NSMutableAttributedString(string: "Hello, [swift].[playground]")
if let textInArray = ["swift", "playground", "others"] {
    for text in textInArray {
        attributedString.highlightTarget(text, color: UIColor.blueColor())
    }
}

//swift 5

extension NSMutableAttributedString {

func highlightTarget(target: String, color: UIColor) -> NSMutableAttributedString {
    let targetValue = String(target.dropFirst().dropLast())
    let regPattern = "\\[\(targetValue)\\]"
    if let regex = try? NSRegularExpression(pattern: regPattern, options: []) {
        let matchesArray = regex.matches(in: self.string, options: [], range: NSRange(location: 0, length: self.length))
        for match in matchesArray {
            let attributedText = NSMutableAttributedString(string: targetValue)
            attributedText.addAttribute(NSAttributedString.Key.foregroundColor, value: color, range: NSRange(location: 0, length: attributedText.length))
            self.replaceCharacters(in: match.range, with: attributedText)
        }
    }
    return self
}

}