that's not a subdomain, that's a url path.
A subdomain/subhost would be play.google.com or game.google.com.
For the path the property you are looking for is URL.Path .
Thank for your help
please help me a little more. if i wanna block https:\\chrome.google.com\webstore
what is the url.path chrome or webstore
Here is a copy and paste from this guide, in your case the URL.Path is simply /webstore
You're also gonna want to review this best practice:
URL.Host.BelongsToDomains (example entry)