ios - 如何设置输入时最大数值数

Question

我有一个 UITextField，我想将该字段中允许的最大输入值限制为 1000。例如(1-1000)，如果文本字段中的值超过 1000，则文本字段不应获取如下值输入。我尝试了以下

func textField(_ textField: UITextField,shouldChangeCharactersIn range: NSRange,replacementString string: String) -> Bool
{
    var newString: String = textField.text.replacingCharacters(in: range, with: string)
    var characterSet = CharacterSet(charactersIn: "0123456789,.").inverted
    if (newString as NSString).rangeOfCharacter(from: characterSet).location != NSNotFound {
        return false
    }
    return Double(newString) ?? 0.0 < 1000
}

Answer 1

试试这个。希望这会有所帮助

 func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        guard let text = textField.text else { return true }
        let newLength = text.characters.count + string.characters.count - range.length
        return newLength <= 1001 
    }