Send Binary Data from ASP

One of the more common tasks that we've performed is to send a existing document to the browser. For our client base, the most common document types include Adobe Acrobat (.pdf), Microsoft Word (.doc) and PKZip (.zip). Innately, it is not hard to get these files to the client. Simply using a Response.Redirect to the path for the document works. However, if the documents are kept in a location other than in the hierarchy underneath the web root, there are security considerations that need to be addressed. I don't know about you, but I'd rather look for alternates rather than knowingly expose my site to security holes. As well, if you client has associated the type of the downloaded file with an application on their computer, the document will be automatically opened. In many cases, I would rather have the user save the document in their field system.

Fortunately, we discovered a relatively straightforward option that was open to us. With just a few lines of code, we can not only push binary data directly from ASP, but also force the user to save the document onto their hard drive.