The parameters dictionary contains a null entry for parameter 'productId' of non-nullable type 'Syst
- by Naim
Hi Guys, 
I am trying to implement an edit page in order administrator to modify data in database.Unfortunately I am encountering an error. 
The code below:
public ViewResult Edit(int productId)
        {
           // Do something here 
        }
but I am getting this error: 
"The parameters dictionary contains a null entry for parameter 'productId' of non-nullable type 'System.Int32' for method 'System.Web.Mvc.ViewResult Edit(Int32)' in 'WebUI.Controllers.AdminController'. To make a parameter optional its type should be either a reference type or a Nullable type.
Parameter name: parameters"
I changed my route in Global.asax.cs like this: 
 routes.MapRoute(
"Admin",
"Admin/{action}/{ productId}",
new { controller = "Admin", action = "Edit",  productId= "" }
);
but still I am getting the error 
Thanks for your help!
Naim