PROGRAMATICALLY FINDING OUT THE CURRENT PAGE NUMBER OF AN OPEN PDF FILE

My application lists a number of pdf files, which can be opened for viewing.  

Let's say the user picks "Document A"

Once it is opened, the user views and stops at a certain page. So the user stops at page 10 of "Document A"

The user clicks a button in our application.  

Our application captures the current page number, which is page 10, the user is on.

Is there a way to do this in C#? Or an SDK that is C# compatible that will give me this capability?

Conversely, once we know the page number, we store this number along with a reference of which document that page number belonged to.

At a later time, the user can press a button in my application that will list these references as such:

"Document A"    ----  Page 10

They click the page number and my application opens the document on page 10.

Is this also possible with C#? Or an SDK that is C# compatible that will give me this capability?

Any help would be appreciated!