swift - 在 swift 中屏蔽 textField

Question

如何在 swift 中为文本字段设置掩码？例如，电话文本字段，当用户键入它时显示为电话格式，如 objective-C 中的以下代码:

self.textField.mask = @"(##)####-####";

Answer 1

Swift 4&&5 非常简单的电话号码掩码

您必须将此代码用作文本字段委托(delegate)。

 func formattedNumber(number: String) -> String {
                 let cleanPhoneNumber = number.components(separatedBy: CharacterSet.decimalDigits.inverted).joined()
                 let mask = "## ### ###"
                 var result = ""
                 var index = cleanPhoneNumber.startIndex
                 for ch in mask! where index < cleanPhoneNumber.endIndex {
                     if ch == "#" {
                         result.append(cleanPhoneNumber[index])
                         index = cleanPhoneNumber.index(after: index)
                     } else {
                         result.append(ch)
                     }
                 }
                 return result
             }
             func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string:  String) -> Bool {
                 guard let text = textField.text else { return false }
                 let newString = (text as NSString).replacingCharacters(in: range, with: string)
                 textField.text = formattedNumber(number: newString)
                 return false
             }