How to allow dot input for the 'key' validation

Question

I'm trying to add validation to the entry box (tkinter) for the ip address input. It should only allow 0 - 255 inputs seperated by four dots. but the code which i have does not allow dots in the entry box. Someone help!

import tkinter as tk

def validate_ip( value_if_allowed, validation_type):
    if validation_type == 'key':
        try:
            if value_if_allowed:
                parts = value_if_allowed.split('.')
                if len(parts) <= 4:
                    for part in parts:
                        if not (0 <= int(part) <= 255):
                            return False
                else:
                    return False
        except ValueError:
            return False
    return True

root = tk.Tk()
root.title("IP Address Validation")

validate_ip_entry = root.register(validate_ip)
ip_entry = tk.Entry(root, validate="key", validatecommand=(validate_ip_entry,  '%P',   '%v'))
ip_entry.pack(padx=10, pady=10)

root.mainloop()

It is currently allowing numbers only till 255 but not allowing me to enter dots after that.

Answer 1

You could wrap int(part) in try/except and remove empty parts:

def validate_ip(value_if_allowed, validation_type):
    if validation_type == 'key':
        for part in value_if_allowed.split('.'):
            # ignore empty string from split!
            if not part:
                continue

            # silently convert part to int.
            try:
                part = int(part)
            except ValueError:
                return False

            if not (0 <= int(part) <= 255):
                return False
        return True