McAfee API for ASP.Net

After doing a little digging for you, it doesn't look like the Mcafee API is commonly available.

You need to get in contact directly with them if you want samples, however there are third party tools that can plugin to many other AV scanners such as those available from Opswat which comes with a very good API for many languages.

Edit -

Probably not the best way of going around it, but if you need to use Mcafee (a few other AV's actually provide API's out the box) - You could always just install it on the server and disable all the active scan parts and then just call the scanner exe via command line arguments and wait for a response code - the same way as many download managers, IM clients and others hook into third party anti virus scanners.