Basics
When a http request is made, the following basic flow happen…
MVC Route Handler > Controller
The controller determines the action, if the action result returns a view, the view renderer will return the correct view.
Passing information from Controller to View
- The ViewBag
- ViewDataDictionary
- Strongly typed views with a view model
Strongly typed views with a view model
@using Guestbook.Models // Where the model is stored
@model TypeOfModel // The type of the model
...
<div> @model.FieldName </div>
Dependency Injection with Controllers
Asp.Net Controller Dependency Injection for Beginners
Manual Dependency Injection
Assume we have removed the default constructor on the home controller and instead our home controller has a dependency on persistenceService. We can manually get dependency injection working by doing the following.
- Create a custom controller factory
- Wire up the builder current factory to the custom controller
Create the following custom controller factory…
public class CustomControllerFactory : IControllerFactory
{
readonly persistenceService _persistenceService;
public CustomControllerFactory()
{
_persistenceService = new persistenceService();
}
public IController CreateController(RequestContext requestContext, string controllerName)
{
if (controllerName.ToLowerInvariant().StartsWith("home"))
{
var controller = new HomeController(_persistenceService);
return controller;
}
var defaultFactory = new DefaultControllerFactory();
return defaultFactory.CreateController(requestContext, controllerName);
}
public SessionStateBehavior GetControllerSessionBehavior(RequestContext requestContext, string controllerName)
{
return SessionStateBehavior.Default;
}
public void ReleaseController(IController controller)
{
var disposable = controller as IDisposable;
if (disposable != null)
{
disposable.Dispose();
}
}
}
In the global.asax.cs file make the following changes…
private void RegisterCustomControllerFactory()
{
IControllerFactory controllerFactory =new CustomControllerFactory();
ControllerBuilder.Current.SetControllerFactory(controllerFactory);
}
protected void Application_Start()
{
RegisterCustomControllerFactory();
...
}
Using an IOC container for Dependency Injection
- Add Unity.Mvc4 to the project via nuget
- Register the types in the Bootstrapper.cs file
Using Dependency Injection for Views
For dependency injection in views you need to use property injection.
Create a class that the view will inherit from…
public class DependencyResolvedBasePage : WebViewPage
{
[Dependency]
public IDependentService DependentService {get; set;}
public ovveride void Execute()
{
}
}
In the view have something like…
@inherits DependencyResolvedBasePage
...
