Getting Data from the Request Object in ASP.NET MVC
Most of the time in ASP.NET MVC I can count on model binding to fill in the values for the parameters to my Action methods. Every once in a while, though, model binding doesn't do what I expect. You can create your own custom modelbinder to solve this problem (I've even discussed how to do that for the ASP.NET Web API). However, that may be overkill.
Often you can solve your problem by accessing one (or all) of the collections in ASP.NET's Request object (available in your controller through its Request property). There are a number of collections you can use to access data sent from the browser and their names do a pretty good job of describing what data they hold:
You can also use the Params collection (which combines the values from Cookies, Form, QueryString, and ServerVariables) but you'd be safer with one of the more specific collections. The problem with the Params collection is that you can have the same data stored under the same name in multiple collections (Cookies and QueryString, for example). If you use Params you can't be sure which of those collections your data will come from.
Posted by Peter Vogel on 02/20/2018