ios - characters - swift set text field max length

Estableciendo el número máximo de caracteres de `UITextView` y `UITextField`

Question

Me gustaría establecer un número máximo de caracteres que se pueden escribir tanto en un UITextView como en un UITextField . Este número se mostrará en una pequeña etiqueta (para referencia del usuario, Estilo de Twitter).

Answer 1

Actualizar Swift 4.X

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
    let newText = (textView.text as NSString).replacingCharacters(in: range, with: text)
    let numberOfChars = newText.count
    return numberOfChars < 10    // 10 Limit Value
}

Probar esto:

func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
    let newText = (textView.text as NSString).stringByReplacingCharactersInRange(range, withString: text)
    let numberOfChars = newText.characters.count // for Swift use count(newText)
    return numberOfChars < 10;
}

Answer 2

Probar esto:-

 func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
    print("chars /(textView.text.characters.count) /( text)")

    if(textView.text.characters.count > 20 && range.length == 0) {
        print("Please summarize in 20 characters or less")
        return false;
    }

    return true;
}

Answer 3

Swift 4, Xcode 9.1 GM

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
    adjustFrames()
    return textView.text.count + (text.count - range.length) <= 200
}

Answer 4

SWIFT 4

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
     let newText = (textView.text as NSString).replacingCharacters(in: range, with: text)
     return newText.count < 10
}

Answer 5

Swift 3.0

Simplemente anule esta función UITextFieldDelegate, establezca la variable de límite de caracteres deseada y estará listo:

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool 
{        
        let characterLimit = 5
        let newText = NSString(string: textField.text!).replacingCharacters(in: range, with: string)
        let numberOfChars = newText.characters.count
        return numberOfChars < characterLimit
}

Answer 6

Swift 4 / Xcode 9.1

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {

    let currentText = textView.text ?? ""
    guard let stringRange = Range(range, in: currentText) else { return false }
    let changedText = currentText.replacingCharacters(in: stringRange, with: text)
    return changedText.count <= 399 // Pass your character count here 
}

Answer 7

Swift 4:

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
  let newText = (textView.text as NSString).replacingCharacters(in: range, with: text)
  return newText.count <= 70
}