如何在Swift中限制2个文本字段中的数字？

Question

I want to limit the user's option in the textfield to type only numbers that is less than 59.

Iv'e got a code that works perfectly on only 1 textfield:

func textField(textField: UITextField,
    shouldChangeCharactersInRange range: NSRange,
    replacementString string: String) -> Bool
{
    var startString = ""
    if (minutesTF.text != nil)
    {
        startString += minutesTF.text!
    }
    startString += string
    var limitNumber = startString.toInt()
    if limitNumber > 59
    {
        return false
    }
    else
    {
        return true
    }
}

But my code for 2 textfields does't work right:

func textField(textField: UITextField,
    shouldChangeCharactersInRange range: NSRange,
    replacementString string: String) -> Bool
{
    var startString = ""
    if (minutesTF.text != nil)
    {
        startString += minutesTF.text!
    }
    startString += string
    var limitNumber = startString.toInt()
    if limitNumber > 59
    {
        return false
    }
    else
    {
        return true
    }
}
func textField2(textField: UITextField,
    shouldChangeCharactersInRange range: NSRange,
    replacementString string: String) -> Bool
{
    var startString = ""
    if (secondsTF.text != nil)
    {
        startString += secondsTF.text!
    }
    startString += string
    var limitNumber = startString.toInt()
    if limitNumber > 59
    {
        return false
    }
    else
    {
        return true
    }
}

Answer 1

You can only have one implementation of the shouldChangeCharactersInRange method. So your second one (with the textField2 name in the method) is never called. Delete your textField2:shouldChangeCharactersInRange:replacementString: method.

Note that the text field is passed as a parameter. Use that text field parameter instead of hardcoding the text field ivar in your implementation.

In other words, replace the use of minutesTF with textField .

func textField(textField: UITextField,
    shouldChangeCharactersInRange range: NSRange,
    replacementString string: String) -> Bool
{
    var startString = ""
    if (textField.text != nil)
    {
        startString += textField.text!
    }
    startString += string
    var limitNumber = startString.toInt()
    if limitNumber > 59
    {
        return false
    }
    else
    {
        return true
    }
}