Regex Directory Name Validation [closed]

Question

I want to check if a textbox have a valid directory name. Because I will create a directory with this textbox value.

Another thing, the value must have at least 3 characters and cannot have more than 20 characters.

How can I do it?

Answer 1

Path.GetInvalidPathChars is where you can find out which characters are invalid. Rather than use regex, I suggest you use Path.GetFullPath as this will validate the path for you: invariably it will do a better job than anything you will try to roll yourself and will be kept up-to-date as the rules change over time.

As for its length, use the methods of the Path class to get the component of the path that you want to check.