如何为标签添加样式以快速显示字符串

Question

我想在标签中使用样式编号。如下图所示。 但我没有这个想法。

sample image

Answer 1

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {

  let aSet = NSCharacterSet(charactersInString:"0123456789").invertedSet
  let compSepByCharInSet = string.componentsSeparatedByCharactersInSet(aSet)
  let numberFiltered = compSepByCharInSet.joinWithSeparator("")
  return string == numberFiltered

}