Get user selected phone number from CNContactProperty and extract the phone number from it as a string. first "import ContactsUI" In button action add this code:

import ContactsUI
import UIKit

class PickContactViewController: UIViewController {
    @IBOutlet weak var contactLabel: UILabel!
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    
    @IBAction func handleContact(_ sender: UIButton) {
        let contacVC = CNContactPickerViewController()
        contacVC.delegate = self
        contacVC.displayedPropertyKeys = [CNContactGivenNameKey, CNContactPhoneNumbersKey]
        self.present(contacVC, animated: true, completion: nil)
    }
}

After add CNContactPickerDelegate in your viewcontroller  call function  didSelectContact Or didSelectContactProperty for action select phone number.

didSelectContact - if you need only one phone number
didSelectContactProperty - when the contact has more than one phone number

---didSelectContact (Just get PhoneNumber)

extension PickContactViewController: CNContactPickerDelegate {
// MARK: Delegate method CNContectPickerDelegate if just select 1 phone number
    private func contactPicker(_ picker: CNContactPickerViewController, didSelect contact: CNContact) {
            let numbers = contact.phoneNumbers.first
            print((numbers?.value)?.stringValue ?? "")
            let text = (numbers?.value)?.stringValue.replacingOccurrences(of: "-", with: "", options: NSString.CompareOptions.literal, range: nil)
            let text2 = text?.replacingOccurrences(of: " ", with: "", options: NSString.CompareOptions.literal, range: nil)

            self.contactLabel.text = " Contact No. \(text2 ?? "")"
    }

    func contactPickerDidCancel(_ picker: CNContactPickerViewController) {
        self.dismiss(animated: true, completion: nil)
    }
}

OR
--didSelectContactProperty (Get More ->"Name, email, phone number, etc")

extension PickContactViewController: CNContactPickerDelegate {

    // MARK: Delegate method CNContectPickerDelegate for select more than 1 phone number and username
    func contactPicker(_ picker: CNContactPickerViewController, didSelect contactProperty: CNContactProperty) {

        let phone = contactProperty.contact.phoneNumbers.first?.value.stringValue
        let phoneName = contactProperty.contact.givenName
        print("Phone: \(phone ?? "")", "Name: \(phoneName)")
       self.contactLabel.text = " Contact No: \(phone ?? "")"       
    }

   func contactPickerDidCancel(_ picker: CNContactPickerViewController) {
        self.dismiss(animated: true, completion: nil)
    }

}

Note plus:  Check all contact in one contact name

for check all  -> print(data.value.stringValue)
for check by index -> print(data[0].value.stringValue)

  // check all contact
        contactProperty.contact.phoneNumbers.forEach { data in
            print(data.value.stringValue, "Phone",data[0].value.stringValue)
            
        }

1. Capslock UITexfield Editing changed

- Texfield.autocapitalizationType = .allCharacters
- Texfield.autocapitalizationType = .words // first character
- Texfield.autocapitalizationType = .sentences // first character in line
- Texfield.autocapitalizationType = .none

2. Dynamic tableView in scroll view


// public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
//    haightConstant.constant = haightConstant.constant + tableView.contentSize.height - tableView.layer.frame.size.height
//    return 10
//}

note:
- haightConstant -> height view in scrollview
- haightConstant.constant -> present height view
-  tableView.contentSize.height -> height per cell
- tableView.layer.frame.size.height -> present height tableview


3. HTML To String Swift 4.2

extension String{
    func convertHtml() -> NSAttributedString{
        guard let data = data(using: .utf8) else { return NSAttributedString() }
        do{
            return  try NSAttributedString(data: data, options: [NSAttributedString.DocumentReadingOptionKey.documentType: NSAttributedString.DocumentType.html], documentAttributes: nil)
        }catch{
            return NSAttributedString()
        }
    }
}

how to use:

result.attributedText = htmlStrng.text?.convertHtml()
-OR-
result.attributedText = "how to use:<br /><br />result.attributedText = htmlStrng.text?.convertHtml()<br />-OR-<br />result.attributedText = "".convertHtml()<br /><br /><br />4.?????<br />.convertHtml()


4. Image URL to ImageView without Library

        do {
            let url = URL(string: "http://verona-api.municipiumstaging.it/system/images/image/image/22/app_1920_1280_4.jpg")
            let data = try Data(contentsOf: url!)
            self.imageView.image = UIImage(data: data)
        }
        catch {
            print(error)
        }

Or use an extension

extension UIImageView {
    func load(url: URL) {
        DispatchQueue.global().async { [weak self] in
            if let data = try? Data(contentsOf: url) {
                if let image = UIImage(data: data) {
                    DispatchQueue.main.async {
                        self?.image = image
                    }
                }
            }
        }
    }
}

5. Need Optional in URL 

Example if you found error like this :



Try this solution use if  before let variable

if let url = URL(string: "http://verona-api.municipiumstaging.it/system/images/image/image/22/app_1920_1280_4.jpg") {
            imageView.load(url: url)
        }

6. Background for Stackview

extension UIStackView {

    func addBackground(color: UIColor) {

        let subView = UIView(frame: bounds)

        subView.backgroundColor = color

        subView.autoresizingMask = [.flexibleWidth, .flexibleHeight]

        insertSubview(subView, at: 0)

    }

}

how to use:

// stackview. addBackground(color: UIColor.blue)


7. Multiple Looping Array 

@IBOutlet var titleChild: [UILabel]!  // outlet collection

let dataArrayString: [String] = ["a", "b", "c"]

for (title, data) in zip(titleChild, dataArrayString) {

            title.text = data.uppercased()

  }

8. Set Maximum character in textfield

    override func viewDidLoad() {
        super.viewDidLoad()

        textfield.delegate = self

    }

extension viewController: UITextFieldDelegate {
    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
                let newLength = (textField.text?.utf16.count)! + string.utf16.count - range.length
                if newLength <= 8 { 
                    return true
                } else {
                    return false
                }
            }
    }

9. Regex for phone number 

example: Japan extension country (+81)

   func isPhoneNumbersPrefix() -> String {

        let pattern = "^((?:\\+81|81)|0|[1-9]{0})"

        do {

            let regex = try NSRegularExpression(pattern: pattern, options: [])

            let range = NSRange(location: 0, length: self.count)

            let newString = regex.stringByReplacingMatches(in: self, options: [], range: range, withTemplate: "0")

            return newString

        } catch {

            NSLog("replaceAll error: \(error)")

        }

        return self

    }