Limite la entrada de UITextField a números en Swift

No dudes en compartir nuestro espacio y códigos en tus redes, danos de tu ayuda para ampliar esta comunidad.

Solución:

Puedes usar UITextFieldDelegate‘s shouldChangeCharactersInRange método para limitar la entrada del usuario a números:

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

    // Create an `NSCharacterSet` set which includes everything *but* the digits
    let inverseSet = NSCharacterSet(charactersInString:"0123456789").invertedSet

    // At every character in this "inverseSet" contained in the string,
    // split the string up into components which exclude the characters
    // in this inverse set
    let components = string.componentsSeparatedByCharactersInSet(inverseSet)

    // Rejoin these components
    let filtered = components.joinWithSeparator("")  // use join("", components) if you are using Swift 1.2

    // If the original string is equal to the filtered string, i.e. if no
    // inverse characters were present to be eliminated, the input is valid
    // and the statement returns true; else it returns false
    return string == filtered

---

Actualizado para Swift 3:

 func textField(_ textField: UITextField, 
    shouldChangeCharactersIn range: NSRange, 
    replacementString string: String) -> Bool 

    // Create an `NSCharacterSet` set which includes everything *but* the digits
    let inverseSet = NSCharacterSet(charactersIn:"0123456789").inverted

    // At every character in this "inverseSet" contained in the string,
    // split the string up into components which exclude the characters
    // in this inverse set
    let components = string.components(separatedBy: inverseSet)

    // Rejoin these components
    let filtered = components.joined(separator: "")  // use join("", components) if you are using Swift 1.2

    // If the original string is equal to the filtered string, i.e. if no
    // inverse characters were present to be eliminated, the input is valid
    // and the statement returns true; else it returns false
    return string == filtered  

Para cualquiera que busque una respuesta más corta, he encontrado esto bastante útil.

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool 
    // remove non-numerics and compare with original string
    return string == string.filter("0123456789".contains)

Funciona en XCode 10.1, Swift 4.2

Si entiendes que te ha resultado de ayuda nuestro artículo, nos gustaría que lo compartas con el resto desarrolladores de esta forma nos ayudas a dar difusión a este contenido.

---

---

Utiliza Nuestro Buscador