Bold the text that was serched by the user in iOS swift || change particular string color in the textfield in iOS swift

Solution:

The below function will return the attributed string that was searched by the user with background color change. Also you can change the color of the text.


    func boldSearchResult(searchString: String, resultString: String) -> NSMutableAttributedString {
       
        let attributedString: NSMutableAttributedString = NSMutableAttributedString(string: resultString)
        let pattern = searchString.lowercased()
        let range: NSRange = NSMakeRange(0, resultString.characters.count)
       
        let regex = try! NSRegularExpression(pattern: pattern, options: NSRegularExpression.Options())
       
        regex.enumerateMatches(in: resultString.lowercased(), options: NSRegularExpression.MatchingOptions(), range: range) { (textCheckingResult, matchingFlags, stop) -> Void in
            let subRange = textCheckingResult?.range
            attributedString.addAttribute(NSBackgroundColorAttributeName,value: UIColor.yellow, range: subRange!)
        }
        return attributedString
    }