限制几个文本字段的长度

Question

I have several text fields in one view controller and I'm using the following function to limit the number of characters:

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
    return textView.text.characters.count + (text.characters.count - range.length) <= 300
}

How can I change the number of maximum number of characters for a different text field? I need a lower limit for another text field.

Answer 1

For TextView you need to use following TextView delegate method

func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool
{
     if textView == yourTextViewName
     {
         let str = (NSString(string: textView.text!)).replacingCharacters(in: range, with: text)
         if str.characters.count <= 300 {
             return true
         }
         textView.text = str.substring(to: str.index(str.startIndex, offsetBy: 300))
         return false
     } 
     return true
}

For TextField you have to use following delegate method

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool
{
    if textField == yourTextFieldName {
        let str = (NSString(string: textField.text!)).replacingCharacters(in: range, with: string)
        if str.characters.count <= 300 {
            return true
        }
        textField.text = str.substring(to: str.index(str.startIndex, offsetBy: 300))
        return false
    }
    return true
}

I hope this help you.