Namespace can't be referenced from another namespace in same project - App_Code

Question

I have a project with this folder hierarchy:

Project
 App_Code
  library.cs
 Application
  page.aspx
   page.aspx.cs

The problem is that page.aspx.cs cannot reference a public function in library.cs. I've checked all relevant access modifiers and even tried recreating the App_Code folder and its contents.

I also tried putting library.cs under the same folder as page.aspx.cs, but it still couldn't see into the App_Code namespace.

Answer 1

Basically, the App_Code namespace is reserved by the compiler for certain types of projects.

In this case, it was a web forms project. When I changed the namespace from App_Code to anything else, the reference worked just fine.