Remove characters in inputfield in unity

Question

I have an inputfield in one scene,there I need a formate like MM/YY,when user enters first two integers / should be added immediate to the second character.So I have added following code the inputfield onvalueChanged event

 if (ExpiryDateInputField.text.Length == 2)
        {
            ExpiryDateInputField.text = ExpiryDateInputField.text + "/";

            ExpiryDateInputField.MoveTextEnd(false);
        }

Here the problem is,when I am trying to remove text the text after / is removing but the text before / is not removing,Where I am doing wrong.

Ex: If I enter 1234 the input field will display is as 12/34,when I am trying to remove the entered text 3 and 4 are removing while clicking on backspace on keyboard but 12/ are not removing. Is there any way to work it out?

Answer 1

The problem is basically this.

You enter "12", OnValueChange is called and "/" is added, now you have "12/".

You press backspace to remove the "/", OnValueChange is called and "/" is added, now you have "12/".

You could try remembering the last value of the InputField , and if that value contained a "/", dont append another "/".

string last = string.Empty;

public void OnValueChange()
{
    if (ExpiryDateInputField.text.Length == 2 && !last.Contains("/"))
    {
         ExpiryDateInputField.text = ExpiryDateInputField.text + "/";

        ExpiryDateInputField.MoveTextEnd(false);
    }
    last = ExpiryDateInputField.text;
}