A Web application does not have access to client systems, for a good reason. Imagine for a second that it was possible. Would any reasonable user like that some unknown site could discover printers or other equipment? This even sounds scary.
This article explains how to print using ASP.NET:
Note that the server side only provides printable content, and all the detail of printing selection, printing quality and other options totally happens on the client side, in a way designed in client's OS. This is the only reasonable and safe way.
Even this way seems to be a bit too redundant and intrusive, to my taste. I personally think that the user knows better when to print, what to print and how. You better just provide printer-friendly content. A while ago, some special "printable version" anchors were in fashion, but you should admit that this is not elegant, especially in terms of site maintenance. Much better approach is using CSS media types. Please see:
See also my past answer on the topic:
Print to LPT1 port using ASP.net