我使用 help 方法创建了一个类,可以从项目中的任何位置调用该类。
SWIFT代码:
class TextFieldUtil: NSObject {
//Here I am using integer as max value, but can change as you need
class func validateMaxValue(textField: UITextField, maxValue: Int, range: NSRange, replacementString string: String) -> Bool {
let newString = (textField.text! as NSString).stringByReplacingCharactersInRange(range, withString: string)
//if delete all characteres from textfield
if(newString.isEmpty) {
return true
}
//check if the string is a valid number
let numberValue = Int(newString)
if(numberValue == nil) {
return false
}
return numberValue <= maxValue
}
}
然后您可以在您的 uiviewcontroller 中使用带有任何文本字段验证的文本字段委托方法
func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
if(textField == self.ageTextField) {
return TextFieldUtil.validateMaxValue(textField, maxValue: 100, range: range, replacementString: string)
}
else if(textField == self.anyOtherTextField) {
return TextFieldUtils.validateMaxValue(textField, maxValue: 1200, range: range, replacementString: string)
}
return true
}