I know this has been asked several times may be, but most (if not all) solutions I've seen were involving a javascript solution or disabling form/submit button, which I'm not preferring.
I have couple of huge forms that may take some time to complete submission which may let the user to re-submit many times during the first submission, which eventually will cause for many records in the database.
Proposed solution:
A proposed solution is to have a generic method that have an array including all submitted forms IDs, each time a user submit a form, it's ID will be added to that array if it's not already existed, after the submit complete the ID will be popped out the array. A drawback can be counted on this solution in case a user opened two or more pages of the same form and submit them synchronously, but that can be worried about later.
My question is how feasible is my proposed solution and how good it can be? and how can I implement that generic method?
I understand that Apache Struts 2 framework has some solution to prevent such thing (Token Interceptor), how to do that in MVC 4?:
Just add a GUID field to the ViewModel the view is bound to (You are using ViewModels right?) and every time the empty form is asked for, generate a new GUID (solves the issue of downloading two or more copies by same user) for it and have it included in the view as a hidden field (string representation of it). Then you can implement the array solution you are talking about in a session variable or even a database based solution in which all processed GUIDs are saved in a table that gets cleared every so often, a text file that contains the list of GUIDs, etc. kind of hard to pick a complete solution based on just what you provide. But the above should provide you with all the requirements you have outlined.