Getting file size of file using file url

thank you for reply

The file is not in my project folder physically, I am trying to calculate filesize of online file directly

It gives error as -

System.IO.IOException: The filename, directory name, or volume label syntax is incorrect. : 'D:\EliCoreAPI\Eli-CoreAPI\{mydomain.com}\images\banner\single-welcome.png'

so anyway to get filsize of online file directly, if file is not in project local folder or downloaded ?

thank you !

use this