c# - query string parameter obfuscation

Question

I want to obfuscate one query string parameter in ASP.NET. The site will have a high volume of request, so the algorithm shouldn't be too slow.

My problem is that all the algorithms I found result in unwanted characters (like +/=)

Here is an example of what i want to achieve:

www.domain.com/?id=1844

to

www.domain.com/?id=3GQ5DTL3oVd91WsGj74gcQ

The obfuscated param should only include a-z and A-Z and 0-9 characters.

I know I can encrypt using base64, but this will generate unwanted characters such as / or = or +.

Any idea what algorithm can be used?

Update: I'm aware of UrlEncoding , i want to avoid encoding the string. because that will generate charaters like %F2 or %B2 in the url.

Answer 1

You can use HttpServerUtility.UrlTokenEncode and HttpServerUtility.UrlTokenDecode

Encode uses base64 encoding, but replaces URL unfriendly characters.

There's a similar answer in a previous SO question. See the accepted answer.