To upload the files without a POST request (page refresh) you would need a client-side framework. JavaScript is one of them. You should be using jQuery, to make things easier.
You can create a new ajax request (Ajax request is required, there is no other way for you to send the data to the server without creating a new ajax request). You can pass the form data to that request, and it will send the data on to your servers.
It is a little technical thing to understand and conceptualize in the beginning but as time passes you will understand. Read my article on sending the files to the server using jQuery:
Uploading the files – HTML5 and jQuery way![
^].
As far as storing the files on the server is concerned, I would go with saving the files on the file system, rather than storing the files in the database. The database space is really expensive and costly, and you also have to manage the space efficiently. So wasting those bytes of space would be foolish. I would recommend that you store those files on the file system, which in most of the cases are
Unlimited.
However, I am not understanding why do you need the WCF to involve? If somehow, still you need to consume WCF, you should learn about the client's and their methods to send the data, and all that stuff.
http://msdn.microsoft.com/en-us/library/dd456779%28v=vs.110%29.aspx[
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