Customize view discovery in asp.net core mvc

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In this video we will discuss, How to customize view discovery in ASP.NET Core MVC


Default View Discovery in ASP.NET Core MVC

There are several overloaded versions of View() method in ASP.NET Core MVC. If we use one of the following overloaded versions of View() method, it looks for a view file with the same name as the action method.

• View()
• View(object model)

For example, we are returning a View() from the Details action method of the HomeController. So, by default, MVC looks for a view file with name Details.cshtml in "Views/Home" folder.

public class HomeController : Controller
{
    public ViewResult Details()
    {
        return View();
    }
}

View(string viewName) method

If you do not like this default convention, you can use the overloaded version of the View(string viewName) method, that takes viewName as a parameter, to look for a view file with your own custom name.

In the following example, MVC looks for a view file with name "Test.cshtml" instead of "Details.cshtml". Had we not specified the view name, it would have looked for "Details.cshtml".

public class HomeController : Controller
{
    public ViewResult Details()
    {
        return View("Test");
    }
}

Specifying view file path

With this overloaded version, we can either specify a view name or a view file path. In the following example, we specified the absolute view file path. So in this case, MVC looks for a view file with name "Test.cshtml" in "MyViews" folder. Had we not specified the path to the view file, by default, MVC would look for "Details.cshtml" file in "Views/Home" folder. With the absolute path, the .cshtml extension must be specified.

public class HomeController : Controller
{
    public ViewResult Details()
    {
        return View("MyViews/Test.cshtml");
    }
}

Please note : With the absolute path, to get to the root project directory, we can use / or ~/. So the following 3 lines of code does the same thing

return View("MyViews/Test.cshtml");
return View("/MyViews/Test.cshtml");
return View("~/MyViews/Test.cshtml");

Relative View File Path

When specifying a view file path, we can also use a relative path. With relative path we do not specify the file extension .cshtml. In the following example, MVC looks for Update.cshtml file in "Views/Test" folder.

public class HomeController : Controller
{
    public ViewResult Details()
    {
        return View("../Test/Update");
    }
}

If you want to go back up 2 levels in the folder hierarchy, use ../ twice as shown below. In the following example, MVC looks for "Details.cshtml" in "MyViews" folder in the root project directory

public class HomeController : Controller
{
    public ViewResult Details()
    {
        return View("../../MyViews/Details");
    }
}

Other view() overloaded versions

Overloaded Method	Description
View(object model)	Use this overloaded version to pass model data from the controller to the view. We will discuss passing data to the view from the controller in our next video
View(string viewName, object model)	Pass both the view name and model data.

Next Video : Passing data from the Controller to the View in ASP.NET Core MVC