First of all, you don't "preview" PDF's the way you described, Adobe Acrobat Reader has a plugin that is instanciated by the browser to show the content of the PDF. Likewise, Chrome has it's own PDF reader.
You can use different plugins to "embed" the different viewers in your application. But you will need to install them all on the client side.
But this approach is no preview. And neither is it cross-browser, or cross-platform. And as HTML5 goes in a plugin-less direction, it is not future-proof either.
If you really need a preview, you need to render those files as image on the server and send that image to the client.
I suggets you look for some commercial library or command line tool, that you can call on asp.net server side from c# and create actual preview images (PNG) at the time those files are uploaded. With TIFF you don't need such thing as it is supported by .net, so you have everything to convert it to png.
You can try to find free/open source tools for that, but I doubt you will find any.
These are some commetcial options:
http://rainbowpdf.com/server-based-converter/[
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https://www.woutware.com/cadlib/4.0[
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