Question

I recently noticed the following line in an ASP.NET error stack trace

System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +264

What does the `2 in IDictionary`2 mean?

I also found other classes/files named like that in the codeplex repository of ASP.NET MVC

Answer 1

It’s to indicate generic parameters. For example take a look at this reflection code:

var type = typeof(Dictionary<string, string>).GetInterface("IDictionary`2");