My usecase is actually quite simple.
Let's say I get an input argument like abcdalert(document.cookie); and I want to scrub it off the (document.cookie); part.
What is the most efficient way to do this in ASP.NET C#?
PS: The snippet can be any JS code. Not necessarily alerts.
I recommend the HtmlSanitizer .Net library to apply server side sanitization
https://github.com/mganss/HtmlSanitizer
This library used for cleaning HTML fragments and documents from potential XSS attacks. It uses AngleSharp to parse, manipulate, and render HTML and CSS. It is based on a robust HTML parser that can protect your code from deliberate or accidental "tag poisoning" where invalid HTML in one fragment can corrupt the whole document (which can lead to a broken layout or style)