How to generate Controller wise dll in ASP.NET With MVC

What “controller-wise DLL” usually means in real projects , It does NOT mean one DLL per controller class directly.
It means:

• Grouping controllers by module / feature

• Compiling each module into a separate Class Library (DLL)

• Loading them into the main MVC application

Correct and Recommended Approach (Modular MVC)

Step 1: Create Class Library projects
Create separate Class Library projects for each module.

Example:

• MyApp.Web (Main MVC project)

• MyApp.AdminModule (DLL)

• MyApp.ReportModule (DLL)

• MyApp.UserModule (DLL)

Each module DLL will contain:

• Controllers

• Views (optional – handled separately)

• Business logic

Step 2: Add MVC references to Class Library
In each module project:

• Add reference to:

  • Microsoft.AspNetCore.Mvc (ASP.NET Core)

  • System.Web.Mvc (ASP.NET MVC 5)

Set controller classes as public.

Example (inside AdminModule DLL):

public class AdminController : Controller
{
    public ActionResult Index()
    {
        return View();
    }
}

Step 3: Reference the DLL in Main MVC Project
In MyApp.Web:

• Add reference to:

  • MyApp.AdminModule.dll

  • MyApp.ReportModule.dll

Now MVC can discover controllers from external DLLs.

Step 4: Enable Controller Discovery from DLLs

ASP.NET MVC automatically scans referenced assemblies.
No extra configuration needed if:

• Controllers are public

• Class names end with Controller

• Assembly is referenced

For ASP.NET Core:

services.AddControllers()
        .AddApplicationPart(typeof(AdminController).Assembly);

Step 5: Handle Views (Important)

Controllers can be in DLLs, but Views cannot be embedded easily in MVC 5.

Common solutions:

• Keep Views in main MVC project under:
  /Views/Admin/Index.cshtml

• OR use Razor Class Library (ASP.NET Core only)

Alternative: Area-based DLL separation (Most practical)

Instead of controller-wise DLL, use:

• Area-wise DLL

Example:

• Admin Area ? AdminModule.dll

• Reports Area ? ReportModule.dll

This is clean, scalable, and enterprise-friendly.

When should you use controller-wise DLLs?

Use this approach when:

• Large enterprise application

• Multiple teams working independently

• Plug-in based architecture

• Need independent deployment/versioning

Do NOT use it for:

• Small or medium projects

• Simple CRUD apps

• Beginners

You cannot generate controller-wise DLLs directly.
To do it, you must move each controller into its own Class Library project — each project builds its own DLL.